Measuring Economic Growth in New Zealand

Mawson, Peter Working Paper Measuring Economic Growth in New Zealand New Zealand Treasury Working Paper, No. 02/14 Provided in Cooperation with: The Treasury, New Zealand Government Suggested Citation: Mawson, Peter (2002) : Measuring Economic Growth in New Zealand, New Zealand Treasury Working Paper, No. 02/14, New Zealand Government, The Treasury, Wellington This Version is available at: https://hdl.handle.net/10419/205489 Standard-Nutzungsbedingungen: Die Dokumente auf EconStor dürfen zu eigenen wissenschaftlichen Zwecken und zum Privatgebrauch gespeichert und kopiert werden. Sie dürfen die Dokumente nicht für öffentliche oder kommerzielle Zwecke vervielfältigen, öffentlich ausstellen, öffentlich zugänglich machen, vertreiben oder anderweitig nutzen. Sofern die Verfasser die Dokumente unter Open-Content-Lizenzen (insbesondere CC-Lizenzen) zur Verfügung gestellt haben sollten, gelten abweichend von diesen Nutzungsbedingungen die in der dort genannten Lizenz gewährten Nutzungsrechte. 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If the documents have been made available under an Open Content Licence (especially Creative Commons Licences), you may exercise further usage rights as specified in the indicated licence. https://creativecommons.org/licenses/by/4.0/ Measuring Economic Growth in New Zealand Peter Mawson N EW Z EALAND T REASURY W ORKING P APER 02/14 S EPTEMBER 2002 NZ TREASURY WORKING PAPER 02/14 Measuring Economic Growth in New Zealand MONTH / YEAR September 2002 AUTHOR Peter Mawson The Treasury PO Box 3724, Wellington, New Zealand Email Telephone Fax [email protected] 64-4-471-5288 64-4-499-0992 ACKNOWLEDGEMENTS The author would like to thank Maryanne Aynsley, Iris Claus, Arthur Grimes, Katy Henderson, Dean Hyslop, Nathan McLellan, Grant Scobie, and David Skilling for their helpful comments and suggestions on various draft versions of the paper. NZ TREASURY New Zealand Treasury PO Box 3724 Wellington 6008 NEW ZEALAND Email Telephone Website [email protected] 64-4-472 2733 www.treasury.govt.nz DISCLAIMER The views expressed in this Working Paper are those of the author(s) and do not necessarily reflect the views of the New Zealand Treasury. The paper is presented not as policy, but with a view to inform and stimulate wider debate. WP 02/14 | Measuring Economic Growth in New Zealand i Abstract This paper examines New Zealand’s ranking in the OECD based on real GDP per capita. The fall in ranking experienced by New Zealand implies that real GDP per capita growth in New Zealand has been relatively poor in comparison to other OECD countries. The paper examines the history of New Zealand’s growth rate and explores the differences between various techniques for measuring average growth rates. The approaches are all shown to be variants of the average annual growth rate but differ in terms of the weighting structure used. Ultimately, the most appropriate technique depends on the underlying data generating process. The implications of data construction techniques for measured growth rates are discussed and differences between the growth rates obtained from different data sources are illustrated. The paper also illustrates the sensitivity of New Zealand growth rates to the sample period chosen. JEL CLASSIFICATION O47 – Measurement of Economic Growth; Aggregate Productivity C10 – Econometric and Statistical Methods: General KEYWORDS Economic Growth; Measuring Growth; International Comparisons WP 02/14 | Measuring Economic Growth in New Zealand ii Table of Contents Abstract ...............................................................................................................................i Table of Contents...............................................................................................................ii List of Tables......................................................................................................................ii List of Figures ...................................................................................................................iii 1 Introduction...............................................................................................................1 2 New Zealand’s place on the OECD ladder..............................................................2 3 Calculating Growth Rates ........................................................................................4 3.1 Least Squares Growth Rates......................................................................................... 5 3.2 Log Difference Model Growth Rates.............................................................................. 7 3.3 The Average Annual Growth Rate ................................................................................. 8 3.4 Geometric Average Growth Rates................................................................................. 8 3.5 The four approaches summarised ................................................................................. 8 3.6 Choice of Method ......................................................................................................... 11 4 Data Construction Techniques and Measured Growth Rates ............................12 4.1 Changes in the way New Zealand real GDP is measured .......................................... 16 4.2 Different approaches to constructing real GDP series (Chain versus Fixed weights)......................................................................................................... 16 5 Measured New Zealand growth rates over time ..................................................20 6 Conclusion ..............................................................................................................23 References........................................................................................................................24 Appendix A:......................................................................................................................25 A.1 Weighting Scheme of the OLS Growth Rate Estimator................................................... 25 A.2 Obtaining the growth rate estimator in a log-difference model........................................ 26 A.3 The geometric Average Growth Rate .............................................................................. 27 A.4 Proof that Log Difference Regression and Geometric Growth Rates are Equal............. 28 Appendix B - New Zealand real GDP per capita series ................................................29 Appendix C – New Zealand average annual change growth rates from different data sources............................................................................................................30 Appendix D – New Zealand growth rates and growth rate rankings from alternative data sources.........................................................................................31 List of Tables Table 1 – New Zealand’s GDP per Capita Ranking Amongst OECD Countries................................ 3 Table 2 – four techniques to construct a growth rate ......................................................................... 9 Table 3 – A comparison of New Zealand growth rates using the alternative techniques to construct a period growth rate................................................................................................ 10 Table 4 - Unit Root tests on the natural log of New Zealand real GDP per capita series................ 12 Table 5– Sources of New Zealand real GDP per capita data used in this paper............................. 13 WP 02/14 | Measuring Economic Growth in New Zealand iii Table 6 – Example of a Laspeyres Index ......................................................................................... 17 Table 7 – Example of a Paasche Index............................................................................................17 Table 8 – Comparison of annual growth rates for fixed weight real gross domestic expenditure series with different base years.......................................................................... 18 Table 9 - New Zealand Growth Rates for Different Window Endpoints and Window Lengths based on OECD data ............................................................................................................. 20 Table 10New Zealand’s growth rate ranking in the OECD for a number of different subperiods based on OECD data ................................................................................................ 21 Table D1 - New Zealand Growth Rates for Different Window Endpoints and Window Lengths based on PWT data................................................................................................................ 31 Table D2New Zealand’s growth rate ranking in the OECD for a number of different subperiods based on PWT data................................................................................................... 32 Table D3 - New Zealand Growth Rates for Different Window Endpoints and Window Lengths based on Maddison 2001 data............................................................................................... 33 Table D4New Zealand’s growth rate ranking in the OECD for a number of different subperiods based on Maddison 2001 data.................................................................................. 34 Table D5 - New Zealand Growth Rates for Different Window Endpoints and Window Lengths based on Haugh’s Calibrated data......................................................................................... 35 List of Figures Figure 1 – New Zealand’s Real GDP per Capita Ranking Amongst OECD Countries...................... 2 Figure 2 – Weighting Scheme for OLS growth rate estimate (T=20)................................................. 6 Figure 3 – Maximum/Minimum Weight Ratio for time series of length T............................................ 6 Figure 4 -A comparison of different growth rate construction techniques (NZ growth rates measured over different 10 year windows) ............................................................................ 11 Figure 5 – A comparison of New Zealand’s growth rates obtained from different data sets (NZ growth rates measured over different 10 year windows) ................................................ 14 Figure 6 – A comparison of New Zealand’s growth rates obtained from different data sets (NZ growth rates measured over different 10 year windows) ................................................ 15 WP 02/14 | Measuring Economic Growth in New Zealand 1 Measuring Economic Growth in New Zealand 1 Introduction Recently there has been increased interest in New Zealand’s income position relative to other countries, in particular countries in the Organisation for Economic Co-operation and Development (OECD). The increased interest reflects concerns that New Zealand’s relative income position has been falling since the 1950s. For example Growing an Innovative New Zealand (New Zealand Government, 2002) released in February stated that “New Zealand’s relative income declined over much of the post-war period. New Zealand’s real per capita income fell from among the highest in the world in the 1950s, to just under the OECD average in 1970, to 20th in the OECD by 1999.” To address such concerns the previous Government (1999-2002) adopted a goal of returning New Zealand’s per capita income to the top half of the OECD. “ Our economic objective is to return New Zealand’s per capita income to the top half of the OECD and to maintain that standing. This will require New Zealand’s growth rate to be consistently above the OECD average growth rate for a number of years. That will require sustained growth rates in excess of our historical economic performance.” (New Zealand Government, 2002) While such goals focus on New Zealand’s per capita income, the income measure generally used has been Gross Domestic Product (GDP) per capita.1 This paper highlights a number of issues that are relevant when measuring economic growth over time and when making international comparisons on the basis of ranking in real GDP per capita. Section 2 examines New Zealand’s ranking within a group of OECD countries, based on our level of real GDP per capita, when several different data sources are used. This highlights that New Zealand’s ranking is to some extent influenced by the data source used (though all sources are consistent with New Zealand sliding down the ladder over time). The fall in our ranking implies that New Zealand’s growth rate in real GDP per capita must have been relatively poor over periods of time. This leads to the question of what has been New Zealand’s average growth rate since the 1950s and how does this compare with the experience of other countries? However, prior to addressing this question, there are several issues relating to the construction of average growth rates that are important 1 For example New Zealand Government (2002) illustrates New Zealand’s relative decline in per capita income by way of a graph showing New Zealand’s GDP per head. WP 02/14 | Measuring Economic Growth in New Zealand 2 to highlight if a country’s performance is to be accurately assessed. One of these issues is how to measure average growth over any given period of time. This issue is discussed in Section 3. Data construction techniques can have important ramifications for the estimated growth rate. The impact of data construction techniques on measured growth rates are discussed in Section 4. With the issues raised in Sections 3 and 4 borne in mind, Section 5 examines New Zealand’s historical growth performance based on several data sources. Finally, Section 6 concludes by briefly summarising some of the key points. 2 New Zealand’s place on the OECD ladder Figure 1 presents New Zealand’s ranking in the OECD, in terms of real GDP per capita, based on data from three different sources. These different data sources are OECD (2002)2, Maddison (2001), and Penn World Tables (PWT)3. The rankings on which Figure 1 is based are displayed in Table 1. Figure 1 – New Zealand’s Real GDP per Capita Ranking Amongst OECD Countries Regardless of which data source is used, New Zealand’s ranking has dropped over time. Note that in Figure 1 the values on the vertical axis are displayed in reverse order, ie higher numbers (lower rankings) are below lower numbers (higher rankings). Consequently a negative slope is associated with a worsening in the ranking over time. However, there is a degree of variation in New Zealand’s relative ranking across the different data sources. This implies that data construction and collection techniques can influence the particular ranking that New Zealand attains.4 It is also interesting to 2 Data from two tables of this publication were used. OECD($US) rankings are based on Table A.9 of OECD(2002) which presents GDP per head at the price levels and exchange rates of 1995 (US dollars). OECD(PPP) ranking are based on Table B.7 of OECD(2002) which presents GDP per head at the price levels and PPPs of 1995 (US dollars). In both cases data was obtained electronically via OLISNET to enable annual data from 1970 through to 2000 to be used. The Czech Republic, Hungary, Poland and the Slovak Republic are excluded from the sample due to the incomplete time coverage of their data. 3 Alan Heston, Robert Summers, Daniel Nuxoll and Bettina Aten, Penn World Tables Version 5.6, Center for International Comparisons at the University of Pennsylvania, January 1995. 4 Differences in the number of countries included in the various datasets may also lead to different datasets suggesting different rankings. The OECD data displays a ranking out of 26 countries, the PWT data displays a ranking out of 25 countries, and the 0 5 10 15 20 25 1950 1952 1954 1956 1958 1960 1962 1964 1966 1968 1970 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 Year Ranking OECD ($US) OECD (PPP) PWT Maddison(2001) WP 02/14 | Measuring Economic Growth in New Zealand 3 observe that New Zealand’s GDP per capita ranking based on OECD data was substantially higher when 1995 purchasing power parities (PPPs) are used rather than the 1995 exchange rate against the United States dollar. Table 1 – New Zealand’s GDP per Capita Ranking Amongst OECD Countries year OECD ($US) OECD (PPP) PWT Maddison (2001) year OECD ($US) OECD (PPP) PWT Maddison (2001) 1950 3 1976 17 11 10 11 1951 4 1977 17 15 12 14 1952 4 1978 18 16 14 15 1953 7 4 1979 19 18 14 16 1954 4 3 1980 19 18 15 17 1955 6 3 1981 18 18 14 16 1956 7 3 1982 18 18 13 16 1957 6 3 1983 18 18 12 17 1958 7 3 1984 17 18 12 15 1959 7 3 1985 19 18 14 17 1960 3 3 1986 19 18 15 18 1961 4 3 1987 19 18 16 17 1962 5 4 1988 19 19 18 17 1963 4 3 1989 19 19 18 17 1964 5 5 1990 19 19 18 17 1965 4 4 1991 20 19 17 1966 5 3 1992 20 19 17 1967 7 7 1993 20 19 17 1968 7 8 1994 20 19 17 1969 7 7 1995 20 20 17 1970 16 9 8 9 1996 20 20 18 1971 16 9 8 9 1997 20 20 18 1972 16 9 8 9 1998 20 20 18 1973 16 8 7 9 1999 20 20 1974 15 6 7 8 2000 20 20 1975 17 9 7 9 The OECD datasets used in this paper include the following 26 countries (lowest ranking possible is 26): Australia, Austria, Belgium, Canada, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Japan, Korea (South), Luxembourg, Mexico, Netherlands, New Zealand, Norway, Portugal, Spain, Sweden, Switzerland, Turkey, United Kingdom, and the United States. The Penn World Table (PWT) dataset used in this paper is made up of 25 countries (lowest ranking possible is 25). These are the same as for the OECD datasets with the exclusion of Germany. The Maddison dataset used in this paper is made up of 24 countries (lowest ranking possible is 24). These are the same as for the OECD datasets with the exclusion of Iceland and Luxembourg. Ultimately, it appears there will always be a degree of uncertainty as to New Zealand’s actual GDP per capita ranking for any particular individual year back to 1950 (and prior) due to different data sources or differences in the units in which GDP per capita is expressed providing different rankings. This uncertainty also applies to pinpointing subperiods where New Zealand’s ranking decline has been the greatest. Three out of the four series for New Zealand’s GDP per capita ranking display substantial falls in the midto-late 1970s.5 For example, the series based on PWT data shows that New Zealand Maddison data displays a ranking out of 24 countries (as outlined in Table 1). These differences in country numbers are not sufficient to explain the differences between the rankings obtained when using the different datasets, implying that data construction and collection techniques also play a role. 5 The series based on OECD($US) data also displays a falling ranking over this period, although the loss of places is not as great in this series. WP 02/14 | Measuring Economic Growth in New Zealand 10 Table 3 – A comparison of New Zealand growth rates using the alternative techniques to construct a period growth rate Year Real GDP per capita 1970 12921 1971 13204 1972 13646 1973 14423 1974 14980 1975 14458 1976 14457 1977 13835 Window that 1978 13744 Growth is Average Growth Rate (% per annum) Difference compared to AAGR 1979 13695 Measured over AAGR GEO OLS LD GEO & LD OLS 1980 13791 1970-1980 0.70 0.65 0.34 0.65 -0.04 -0.36 1981 14181 1971-1981 0.76 0.72 0.03 0.72 -0.05 -0.74 1982 14673 1972-1982 0.77 0.73 -0.10 0.73 -0.05 -0.88 1983 14874 1973-1983 0.34 0.31 -0.08 0.31 -0.03 -0.43 1984 15454 1974-1984 0.35 0.31 0.33 0.31 -0.03 -0.01 1985 15507 1975-1985 0.73 0.70 0.91 0.70 -0.03 0.18 1986 15807 1976-1986 0.92 0.90 1.36 0.90 -0.03 0.43 1987 15743 1977-1987 1.31 1.30 1.70 1.30 -0.01 0.39 1988 15660 1978-1988 1.33 1.31 1.70 1.31 -0.01 0.37 1989 15687 1979-1989 1.38 1.37 1.55 1.37 -0.01 0.17 1990 15530 1980-1990 1.21 1.19 1.22 1.19 -0.01 0.01 1991 14823 1981-1991 0.47 0.44 0.59 0.44 -0.03 0.12 1992 14829 1982-1992 0.13 0.11 0.06 0.11 -0.02 -0.07 1993 15607 1983-1993 0.52 0.48 -0.09 0.48 -0.03 -0.61 1994 16214 1984-1994 0.51 0.48 -0.05 0.48 -0.03 -0.56 1995 16635 1985-1995 0.74 0.70 0.24 0.70 -0.03 -0.50 1996 16872 1986-1996 0.69 0.65 0.54 0.65 -0.03 -0.15 1997 16972 1987-1997 0.79 0.75 0.90 0.75 -0.03 0.11 1998 16904 1988-1998 0.80 0.77 1.16 0.77 -0.03 0.36 1999 17600 1989-1999 1.20 1.16 1.50 1.16 -0.04 0.31 2000 17938 1990-2000 1.49 1.45 1.84 1.45 -0.04 0.36 1970-2000 1.13 1.10 0.84 1.10 -0.03 -0.29 Note: The GDP per Capita series is GDP per head at the price levels and exchange rates of 1995 (US dollars) as published in (OECD 2002). Data was obtained electronically to 3 decimal places and data to this level of accuracy was used in the growth rate calculations. AAGR, GEO, OLS and LD refer to the growth rate obtained using the Average Annual Growth Rate, Geometric Average, Ordinary Least Squares and Log Difference techniques respectively. Table 3 illustrates the results obtained by using the four growth rate techniques outlined earlier. Estimates of the average growth rate in New Zealand real GDP per capita over a number of different 10-year windows are computed as well as the average growth rate of the entire period (1970-2000). This means that for each window a sub-series of 11 data points is used. Not surprisingly, the growth rates calculated using the geometric average and log difference techniques are identical and only differ to the average annual growth rates by up to 5 one hundredths of a percent. There is substantial variation between the growth rate computed using the OLS technique and the other three techniques. In some cases the difference between the growth rates obtained using the OLS technique and the average annual growth rate technique is greater than the average annual growth rate value. The quadratic weighting scheme used in the OLS technique results in the OLS WP 02/14 | Measuring Economic Growth in New Zealand 11 growth rates being materially different from the growth rates obtained using the other techniques, even when the rates are calculated over the entire sample. Figure 4 -A comparison of different growth rate construction techniques (NZ growth rates measured over different 10 year windows) Source: Author’s growth rate calculations based on OECD data as shown in Table 4. Figure 4 provides an alternative representation of the data in Table 3 and plots the average growth rate in New Zealand’s real GDP per capita for moving 10-year periods as measured using the different growth rate approaches. Thus the first growth rate plotted for each series is for the period 1970 to 1980, the second for the period 1971 to 1981 and so on. Figure 4 again highlights that the growth rate estimates for a particular period can vary significantly depending on the technique used, with the OLS growth rate at times differing substantially from the rates obtained using other approaches. 3.6 Choice of Method Section 3.5 highlighted that growth rates obtained from the OLS approach sometimes differed substantially to those obtained from the other 3 methods. Given this, what is the most appropriate way of calculating a growth rate? This depends on the data generating process underlying the data being used. In the case that the log of GDP per capita is stationary around a deterministic trend and hence does not contain a unit root, then it is appropriate to use the OLS approach. On the other hand when the log of GDP per capita is integrated of order one (I(1)) the log difference approach is more appropriate.12 As the log difference approach provides the same results as the geometric average approach, and is approximately equal to the average annual growth approach, there is little in it when choosing between these three approaches. The average annual growth rate approach involves a weighting structure (standard arithmetic weights) that makes it intuitively simple. The geometric average approach (and consequently log difference approach) is also quite intuitive and has the advantage that if one takes the value of real GDP per capita at the start of the sample period of interest and grow it at the geometric average growth rate for the appropriate number of years, the value obtained will be that of the final value of real GDP per capita in the sample period of 12 Regression analysis based on time series data implicitly assumes that the underlying data is stationary. When a series is integrated of order 1 (I(1)) taking the first difference will result in a stationary series. -0.50 0.00 0.50 1.00 1.50 2.00 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 Window endpoint Average growth rate (%) over period AAGR GEO(=LD) OLS WP 02/14 | Measuring Economic Growth in New Zealand 12 interest. In general this will not be the case when the other growth rate approaches are used. As shown in Table 4, the natural log of all the New Zealand real GDP per capita series used in this paper are integrated of order 1 (I(1)). What this means is, that with New Zealand data at least, the use of the OLS approach to calculate an average growth rate should be avoided and one of the other 3 approaches used. Due to its simplicity, when growth rates are computed in the rest of this paper the average annual growth rate has been used. Table 4 - Unit Root tests on the natural log of New Zealand real GDP per capita series Real GDP per capita series ADF Test on log of series (levels) ADF Test on log of series (first difference) Order of Integration OECD (PPP) -3.075 (1) -3.224** (0) I(1) OECD ($US) -3.075 (1) -3.224** (0) I(1) Calibrated -1.633 (0) -2.630* (0) I(1) Maddison (2001) -2.269 (1) -7.059** (0) I(1) Penn World Tables -1.794 (1) -5.376** (0) I(1) Preliminary PWT -1.654 (1) -6.048** (0) I(1) Both a constant and trend were included in the Augmented Dickey-Fuller (ADF) tests when conducted on levels data. Numbers in brackets in the second and third columns indicate number of lags used in these tests. The lag lengths were determined using the Schwarz criterion. * signifies a unit root null is rejected at the 5% significance level ** signifies a unit root null is rejected at the 1% significance level 4 Data Construction Techniques and Measured Growth Rates Section 3, examined different techniques to estimate an average growth rate over a particular period. Figure 4 highlighted that when these different techniques were applied to a common data series, the OLS approach could result in average growth estimates that looked quite different to those obtained from the other approaches. That is, the choice of average growth rate estimation technique can be quite important. Another factor that must be borne in mind is what dataset to use when calculating average growth rates over a period. For example, there exist several potential series for New Zealand’s real GDP per capita and these series differ in the length of their coverage and how real GDP per capita has been measured13. This section illustrates the differences in New Zealand’s growth rate in real GDP per capita when different data sets are used. Six data sets are used in this illustration. Their details are shown in Table 5. 13 For some longer series the way in which GDP per capita is measured may not be consistent across the whole series, raising doubts about the validity of some comparisons across time. WP 02/14 | Measuring Economic Growth in New Zealand 13 Table 5– Sources of New Zealand real GDP per capita data used in this paper Dataset Source Coverage Additional Details OECD($US) Year beginning 1 April 1970 to year beginning 1 April 2000 GDP per capita at the price levels and exchange rates of 1995 (US dollars) As published in OECD(2002) although data obtained electronically through OLISNET OECD(PPP) Year beginning 1 April 1970 to year beginning 1 April 2000 GDP per capita at the price levels and purchasing power parities (PPP) of 1995 (US dollars) As published in OECD(2002) although data obtained electronically through OLISNET Calibrated chain-weighted real production GDP per capita series Year beginning 1 April 1978 to year beginning 1 April 1999 Annual real GDP series obtained by aggregating Haugh (2001)’s quarterly series. Per capita adjustment made using population data. Maddison(2001) Year beginning 1 April 1950 to year beginning 1 April 1998 GDP per capita in 1990 GearyKhamis dollars. As published in Maddison (2001). Penn World Tables (PWT5.6)14 1950 to 1992 The variable RGDPCH is used. This is Real GDP per capita in constant dollars (Chain Index) expressed in international prices, base 1985. Preliminary Penn World Tables (PWT6.0) 15 1950 to 1997 The variable RGDPCH is used. This is defined as Real per capita GDP chain method (1996 prices). This dataset is yet to be finalised but updates and extends the time coverage of the previous PWT release. The New Zealand series described in this table are presented in Appendix B. For each of these series New Zealand’s average growth rate over every possible ten-year window has been calculated using the average annual growth rate (AAGR) approach outlined in Section 3. As the series are of different lengths the number of possible windows for each series also differs. Figure 5 shows the average growth rate for each ten-year period plotted against the window endpoint.16 This means that a value for, say, 1990 represents the average growth rate over the period 1980 to 1990. Likewise, a value 14 Alan Heston, Robert Summers, Daniel Nuxoll and Bettina Aten, Penn World Tables Version 5.6, Center for International Comparisons at the University of Pennsylvania, January 1995. 15 Alan Heston, Robert Summers and Bettina Aten, Penn World Table Version 6.0, Center for International Comparisons at the University of Pennsylvania, December 2001 16 Appendix C provides the numerical values plotted in Figures 5 and 6. WP 02/14 | Measuring Economic Growth in New Zealand 14 for 1970 represents the average growth rate over the period 1960 to 1970. Figure 5 illustrates the variation between the average growth rate for a ten-year period when different data sets are used. One feature of Figure 5 is that there appears to be more variability in the growth rates obtained using different data sets earlier on in the sample. This is particularly the case if one omits the preliminary Penn World Table data that is yet to be finalised. However, it is worth pointing out that as the graph displays the average growth rate for a ten-year period even small differences would result in material differences in real GDP per capita over time. For example, even when we exclude the preliminary Penn World Table data, the average growth rate for the period ending 1992 (ie 1982 to 1992) differs between data sources by up to a bit under 0.5% per annum. If actual performance was to differ by this much then real GDP per capita would have increased by nearly 5% more over the ten year period when comparing performance for this period under the highest and lowest growth estimates. Figure 5 – A comparison of New Zealand’s growth rates obtained from different data sets (NZ growth rates measured over different 10 year windows) Note: The average annual growth rate method was used to obtain the average growth rates presented in this figure. -1 0 1 2 3 4 1960 1965 1970 1975 1980 1985 1990 1995 2000 Calibrated Maddison01 OECD PWT5.6 Prelim. PWT6.0 Annual average growth rate (%) Window Endpoint WP 02/14 | Measuring Economic Growth in New Zealand 15 Figure 6 – A comparison of New Zealand’s growth rates obtained from different data sets (NZ growth rates measured over different 10 year windows) Note: The average annual growth rate method was used to obtain the average growth rates presented in this figure. Vertical axis displays annual average growth rate (%) Horizontal axis displays year of window endpoint Figure 6 illustrates the growth rates for each series shown in Figure 5 separately (using consistent scales). Casual observation of the Maddison and PWT plots in Figure 6 could suggest a downward trend over time in New Zealand’s average growth rate. However such a conclusion is likely to be misleading due to changes over time in the way in which real GDP for New Zealand has been measured. -1 0 1 2 3 4 1960 1970 1980 1990 2000 Calibrated -1 0 1 2 3 4 1960 1970 1980 1990 2000 Maddison01 -1 0 1 2 3 4 1960 1970 1980 1990 2000 OECD -1 0 1 2 3 4 1960 1970 1980 1990 2000 PWT5.6 -1 0 1 2 3 4 1960 1970 1980 1990 2000 Prelim. PWT6.0 WP 02/14 | Measuring Economic Growth in New Zealand 16 4.1 Changes in the way New Zealand real GDP is measured Over time there have been efforts to improve the way real GDP is measured. Unfortunately, however, these improvements mean that real GDP series constructed on a consistent basis and covering a long historical time period are not available. Consequently long time series of annual GDP data either tend to include data constructed in several different ways or require a considerable proportion of the series to be based on estimated rather than measured values. Statistics New Zealand released upgraded national accounts at the end of 2000 and in mid 2001. These introduced a number of important changes, including moving from a fixed weight to a chain linked calculation of constant price (real) data, the adoption of the international accounting standard, System of National Accounts 1993 (SNA93), and the Australia New Zealand Standard Industrial Classification (ANZSIC). Real GDP figures back as far as the June quarter of 1987 are available on this consistent basis. These new SNA93 chain linked series are now New Zealand’s official data series and replace the previous official series that was based on a different accounting standard called System of National Accounts 1968 (SNA68). The previous official series was also a fixed weight rather than chain weighted series (more details of what this means are provided below). The previous official fixed weight series was available from September 1977.17 What this means is that real GDP series that provide estimates of New Zealand’s real GDP for time intervals that include 1977 are likely to include data that is constructed in several different ways. When this is the case, estimates of economic performance for different sub periods are probably not strictly comparable and unfortunately there is no easy way around this. 4.2 Different approaches to constructing real GDP series (Chain versus Fixed weights) and their influence on growth rates Annual GDP series measure the total value of goods and services produced in an economy over a 12-month period. Nominal GDP series simply sum over all possible goods and services the total value of each type of good or service produced in the 12 months. For each good or service, the total value is the number of units of the good or service produced, multiplied by the price of a unit of that good or service for that year. An increase in nominal GDP from one year to the next can therefore be attributed to an increase in prices, an increase in the volume of goods and services produced, or most probably, some combination of these two. For example, if in year 2 all prices are 10% higher than they were in year 1, and the same quantity (volume) of each good or service is produced, then nominal GDP will be 10% higher. If these goods and services must be shared amongst the same number of people in each year, is the country better off? The answer is no as in aggregate people have the same quantity of goods and services available for consumption. Real GDP series overcome this problem by removing the impact of price changes. Consequently, changes in real GDP reflect changes in the volume or quantity of goods and services produced. Such a series is commonly referred to as being expressed in constant prices or real terms. There are several approaches to doing this, with the approaches differing in the choice of which year’s prices are used in the construction of 17 The calibrated real GDP series produced by Haugh (2001) comprises of “Statistics New Zealand ‘s quarterly chain series from June 1987 onwards appended to a calibrated chain series for the period back to September 1997. The latter is derived by exploiting the statistical relationship between the period of overlapping chain and fixed series (1987:2 to 2000:2).” (Buckle, Haugh and Thomson, 2001) WP 02/14 | Measuring Economic Growth in New Zealand 17 the index.18 As is illustrated below, the choice of which year’s prices are used has implications for the growth rates that can be obtained from the series. This section begins by considering the difference between two types of volume indexes (the Laspeyres and Paasche indexes). A Laspeyres index calculates the total value of GDP holding prices constant at their first year levels. Table 6 presents a theoretical example of real GDP in the first and second year constructed using the Laspeyres method (note the total value of each commodity for each year utilises the first year’s prices). In the example, real GDP has grown by 18.1%. Table 6 – Example of a Laspeyres Index Year 1 Year 2 Quantity q1 Price p1 Value p1q1 Quantity q2 Value p1q2 Commodity A 10 8 80 15 120 B 15 12 180 15 180 C 20 5 100 25 125 Total (real GDP) 360 425 Source: Statistics New Zealand (1998) - with very minor amendments A Paasche index calculates the total value of GDP holding prices constant at their second (or last) year levels. Table 7 presents a theoretical example of real GDP in the first and second year using the Paasche method (note the total value of each commodity for each year utilises the last (second) year’s prices). In the example, real GDP has grown by 15.4%. Table 7 – Example of a Paasche Index Year 1 Year 2 Quantity q1 Value p2q1 Quantity q2 Price p2 Value p1q2 Commodity A 10 60 15 6 90 B 15 210 15 14 210 C 20 120 25 6 150 Total (real GDP) 390 450 Source: Statistics New Zealand(1998) - with very minor amendments Clearly the growth rate is dependent on which approach (Laspeyres or Paasche) is used. The result that the growth rate of the Laspeyres index is greater than the growth rate shown by the Paasche index is not just due to the construction of the example19. The reason why Laspeyres indexes tend to exhibit higher growth than Paasche indexes is due to the substitution effect that occurs when relative price changes occur. People tend to purchase more of goods that have become relatively cheaper and less of goods that have become relatively more expensive. Consequently goods that have become relatively cheaper tend to have faster growth (in terms of numbers of units produced and consumed) and goods that have become relatively more expensive tend to have slower growth. By using first year prices (before the relative price changes), the Laspeyres approach gives a higher weight to fast growing commodities and a smaller weight to slow growing commodities. 18 This discussion relies heavily on Statistics New Zealand (1998). 19 Note that the physical quantities of the goods produced are the same in both Tables 6 and 7. WP 02/14 | Measuring Economic Growth in New Zealand 18 In terms of what drives differences in the growth rates obtained from the two approaches, Statistics New Zealand (1998) states “What matters is the extent to which the pattern of relative prices (ie the ratio of the price of one commodity to another) changes over time and not the general rate of inflation. If all prices were to increase at the same rate the two volume indices would be equal, but if some prices go up faster than others, and especially if some go down while others go up, the two volume indices will diverge. The more variation there is in the price changes, the more the volume indexes will diverge.” Things become even more complex when one is interested in constructing values for real GDP over more than 2 periods. There are two general approaches. The first is known as the fixed weight index approach and uses the prices of just one period. Real GDP for each period in the series is calculated by multiplying the price of each commodity (in the chosen base year) by the quantity of the commodity produced in the year for which real GDP is being calculated. Until recently, this is the approach that Statistics New Zealand used and when using this approach 1991/1992 was chosen as the base year’s prices to be used. For each year, the quantity of a particular commodity produced was multiplied by that commodity’s 1991/1992 price. Summing this product over all commodities gave a value for real GDP expressed in 1991/1992 prices. Consequently, the values of real GDP prior to 1991/1992 are constructed using the Paasche index approach (as the 1991/1992 prices being used relate to a later period than the quantities of commodities produced). On the other hand, values of real GDP for years after 1991/1992 utilise the Laspeyres index approach. As a Laspeyres index tends to register higher growth rates than a Paasche index, this means that it is likely that growth prior to 1991/92 (based on a Paasche index) would be understated to growth post 1991/1992 (based on a Laspeyres index). One issue that arises with fixed weight series is that the growth rates between consecutive years are sensitive to the choice of base year chosen. “In general, moving the base year forward in time will tend to reduce growth rates previously recorded so that they have to be revised downwards. History is rewritten.” (Statistics New Zealand, 1998) Statistics New Zealand (1998) provides an illustration of this by comparing annual growth rates for total real gross domestic expenditure when 1991/92 prices were used with the growth rates when 1982/83 prices are used.20 Table 8 reproduces a table summarising the results. As can be seen from the table the differences in annual growth rates are quite substantial. Table 8 – Comparison of annual growth rates for fixed weight real gross domestic expenditure series with different base years Year ended March Published baseweighted series in 1982/83 prices: percent growth from previous year Published baseweighted series in 1991/92 prices: percent growth from previous year Difference 1988 2.8 0.8 -2.0 1989 1.6 1.1 -0.5 1990 1.1 -0.1 -1.2 1991 -0.9 -0.8 0.1 1992 -0.9 -1.1 -0.2 1993 0.6 0.8 0.2 Source: Based on Table C from Statistics New Zealand (1998) The second general approach to obtaining real GDP values for multiple years is known as the annual chain-linked approach and this method updates the price weights used every 20 Unfortunately this is not a pure experiment as changes to methodology and revisions to component series also contribute to differences in growth rates. WP 02/14 | Measuring Economic Growth in New Zealand 19 year. For the period 1987 to 2000, the chain-linked real GDP series is derived by calculating the (percentage) change between 1987 and 1988 using 1987 prices to value the quantities in 1987 and 1988. The change between 1988 and 1989 is calculated using 1988 prices to value the quantities in 1988 and 1989 and so on. To obtain a series of real GDP figures based on 1995 prices the following approach is used. For each year a measure of the total change between the year of interest and the year 1995 is obtained by multiplying together the annual changes between consecutive years. For years prior to 1995, the value of 1995 real GDP (which will equal the nominal GDP for 1995 as 1995 prices are being used) is divided by the by the appropriate total change figure. For years post 1995 the 1995 value for real GDP is multiplied by this amount. 21 Note that the above approach to obtaining a chain-linked series is known as a Laspeyres chain linked approach as for each pair of years the prices of the earlier year are used. If the latest year’s prices were used for each pair the resulting index would be a Paasche chain index. If relative prices change monotonically using chain weights instead of fixed weights tend to result in a growth rate somewhere between that of a fixed Laspeyres or fixed Paasche index. As outlined above, Statistics New Zealand has upgraded New Zealand’s National Accounts by moving from fixed to (Laspeyres) chain weights. Theoretically this should increase growth rates prior to 1991/92 as a chain Laspeyres index will produce higher growth rates than a fixed Paasche. The upgrade would also theoretically reduce growth rates after 1991/1992 as a chained Laspeyres index will result in lower growth rates than a fixed Laspeyres index. Experimental work by Statistics New Zealand based on real (expenditure based) GDP series showed that when moving from a fixed weight method to a Laspeyres chain weighted method for constructing real GDP series the differences in (annual) growth rates are less than 0.3 percentage points although the annual growth rate between the 1994 and 1995 March years was as high as 0.6 percentage points (see Statistics New Zealand (1998) for more details).22 The key point to be taken from this section is that there are a number of measurement issues associated with measuring real GDP and consequently with measuring the growth in real GDP per capita. As a result there probably does not exist a definitive or ‘true’ calculated value for the historical rate of growth in a particular period. Different approaches to measuring or constructing real GDP series have resulted in the various series for real GDP per capita that are available not being identical. Therefore, the average growth rate for a period of interest will tend to vary across series. 21 Consider the following example. 1992 GDP measured in 1991 prices is 5% higher than 1991 GDP. 1993 GDP measured in 1992 prices is 4% higher than 1992 GDP. 1994 GDP measured in 1993 prices is 6% higher than 1993 GDP. 1995 GDP measured in 1994 prices is 1% higher than 1994 GDP. Consequently 1995 real GDP is 1.05 x 1.04 x 1.06 x 1.01 = 1.169 times as great as 1991 real GDP. If GDP in 1995 was $100 billion then 1991 real GDP would be $85.54 billion. 22 Note that the Statistics New Zealand publication interprets the difference between, say, 1.2% and 1.4% as being 2 percentage points. A more common interpretation of a percentage point would be the difference between, say, 2% and 3% and therefore the difference between 1.2% and 1.4% would be regarded as 0.2 percentage points. In this paper I have used this more common interpretation and therefore have amended the percentage point differences presented in the Statistics New Zealand publication accordingly. WP 02/14 | Measuring Economic Growth in New Zealand 26 Using the definition of t w we get: ∑ ∑ ∑ ∑ = − = = = − −+ = − − =T t sT t T t T st s tt tst tt tt k 1 2 0 1 2)( )( )( )( (A.1.5) By making use of 6 )12)(1( 1 2++ = ∑ = TTT t T t and )1( 2 1+= Tt it can be shown that: )1)(1( )1)(1(6 −+ −+− =TTT ssT ks where Ts ,...,3,2= (A.1.6) Therefore: ∑ = ∆ −+ −+− = T s s Y TTT ssT 2 ln )1)(1( )1)(1(6 ˆ β (A.1.7) A.2 Obtaining the growth rate estimator in a log-difference model The OLS estimator for the model tt Y ε β +=∆ln can be found as follows: β ε −∆= tt Yln (A.2.1) Therefore: 2 2 2)ln( ∑∑ −∆= = βε t T t tY (A.2.2) Differentiating with respect to β gives: ∑ ∑ = =−∆−= ∂ ∂T t t T t t Y 2 2 2 )ln(2 β β ε (A.2.3) Minimisation requires setting (A.2.3) to zero. Therefore: 0)ln( 2 ∑ = =−∆ T t t Y β (A.2.4) Thus: ∑∑ == ∆= T t t T t Y 22 )ln( β (A.2.5) and so: WP 02/14 | Measuring Economic Growth in New Zealand 27 ∑ = ∆ − = T t t Y T2 )ln( 1 1 ˆ β (A.2.6) A.3 The geometric Average Growth Rate Solving the compound growth formula for the growth rate r is one possible way of calculating the average annual growth rate over a period. Outlined below is why this solution for r is known as a geometric average growth rate. We begin with the compound growth rate formula: 1 1)1( − += T TrYY (A.3.1) which can be rewritten as: 1 1 )1( Y Y rT T=+ − (A.3.2) This is equivalent to: 1 2 1 )1( − = −Π =+ t t T t T Y Y r as 12 1 3 4 2 3 1 2 1 ... −− − = t t t tt Y Y Y Y Y Y Y Y Y Y Y Y (A.3.3) Note: the numerator in each fraction cancels with the denominator in the following fraction, except at the endpoints. Therefore by adding and subtracting 1−t Y to the numerator: 1 11 2 1 )1( − −− = −+− =+ Πt ttt T t T Y YYY r (A.3.4) so that: ∏ =− − −       − +=+ T tt tt T Y YY r 21 1 11)1( (A.3.5) 1 1 21 1 11 − =− −                − +=+ ∏T T tt tt Y YY r (A.3.6) WP 02/14 | Measuring Economic Growth in New Zealand 28 A.4 Proof that Log Difference Regression and Geometric Growth Rates are Equal The log difference regression estimate of the growth rate can be found using the following expression: 1 2 ln 1 1 −= ∑∆ −= T t t Y T LD er (A.4.1) now ∑∑∑ =− = − =        − =− − =∆ − T tt t T t tt T t tY Y T YY T Y T21 2 1 2 ln 1 1 )ln(ln 1 1 ln 1 1 as       =− B A BA ln)ln()ln( and 1 1 1 2 21 )(lnln 1 1− − = =−        =         −Π ∑T t t T t T tt t Y Y Y Y T (by using the rules )ln()ln()ln( ABBA =+ and )ln()ln( A BBA =). Consequently (A.4.1) can be rewritten as: 1 1 1 )(ln 1 2−= −         − = ΠT Y Y LD t t T t er (A.4.2) which can be simplified further to: 1 1 1 1 2 −         =− − = ΠT t t T t LD Y Y r (A.4.3) Noting that 12 1 3 4 2 3 1 2 1 2 ... −− − − = = Πt t t t t t T tY Y Y Y Y Y Y Y Y Y Y Y and observing that the numerator in each fraction cancels with the denominator in the following fraction, except at the endpoints, we get: GEO T T LD r Y Y r=−         =−1 1 1 1 (A.4.4) WP 02/14 | Measuring Economic Growth in New Zealand 29 Appendix B - New Zealand real GDP per capita series year OECD ($US) OECD (PPP) calibrated Maddison PWT5.6 prelim. PWT6.0 1950 8453 6667 9313 1951 7651 6263 8762 1952 7792 6074 8578 1953 7850 6068 8529 1954 8734 6811 9471 1955 8714 6878 9628 1956 8981 6772 9503 1957 9030 7010 9796 1958 9168 6926 9720 1959 9614 7040 9883 1960 9444 7960 11152 1961 9767 8066 11561 1962 9744 8154 11465 1963 10149 8387 11976 1964 10430 8677 12365 1965 10901 9032 13001 1966 11381 9121 13550 1967 10683 8704 12591 1968 10565 8624 12398 1969 11546 9122 13437 1970 12920.52 13419.60 11221 9392 13226 1971 13203.61 13713.62 11622 9726 13728 1972 13646.05 14173.15 11916 10004 14101 1973 14423.30 14980.42 12513 10631 14972 1974 14980.18 15558.81 12991 11088 15626 1975 14458.50 15016.98 12613 10526 14804 1976 14456.98 15015.40 12801 10631 15036 1977 13834.62 14369.00 12130 10045 14232 1978 13743.54 14274.40 20472.08 12175 10036 14217 1979 13695.07 14224.06 20907.00 12388 10342 14632 1980 13791.31 14324.02 20989.02 12449 10362 14647 1981 14181.31 14729.08 21872.27 13000 10815 15291 1982 14672.97 15239.73 21795.25 13135 10896 15427 1983 14873.91 15448.43 22191.76 13315 11004 15644 1984 15454.24 16051.18 23175.52 13834 11446 16310 1985 15506.79 16105.76 23303.26 13881 11443 16320 1986 15807.41 16417.99 23793.83 14151 11704 16609 1987 15743.12 16351.21 23714.43 14093 11688 16483 1988 15660.44 16265.35 23661.37 13995 11501 16211 1989 15687.00 16292.93 23620.69 14040 11762 16283 1990 15530.34 16130.22 23330.11 13825 11513 15931 1991 14822.98 15395.53 22760.87 13162 11054 15457 1992 14828.62 15401.40 22586.06 13140 11363 15520 1993 15607.28 16210.13 23767.08 13640 16345 1994 16214.20 16840.50 24692.40 14253 17056 1995 16635.06 17277.61 25335.85 14593 16265 1996 16871.59 17523.28 25693.41 14838 16407 1997 16971.85 17627.41 25852.54 14971 16519 1998 16904.23 17557.18 25754.24 14779 1999 17600.50 18280.34 26803.92 2000 17937.70 18630.57 WP 02/14 | Measuring Economic Growth in New Zealand 30 Appendix C – New Zealand average annual change growth rates from different data sources Period Calibrated Maddison 2001 OECD PWT5.6 Prelim. PWT6.0 1950 - 1960 1.24 1951 - 1961 2.53 1952 - 1962 2.32 1953 - 1963 2.66 3.40 3.55 1954 - 1964 1.81 2.52 2.77 1955 - 1965 2.29 2.83 3.12 1956 - 1966 2.42 3.08 3.67 1957 - 1967 1.75 2.28 2.66 1958 - 1968 1.49 2.30 2.58 1959 - 1969 1.93 2.72 3.25 1960 - 1970 1.83 1.71 1.81 1961 - 1971 1.84 1.93 1.82 1962 - 1972 2.12 2.10 2.18 1963 - 1973 2.20 2.45 2.35 1964 - 1974 2.31 2.53 2.46 1965 - 1975 1.57 1.61 1.42 1966 - 1976 1.27 1.62 1.16 1967 - 1977 1.36 1.52 1.33 1968 - 1978 1.51 1.60 1.47 1969 - 1979 0.76 1.33 0.93 1970 - 1980 1.09 0.70 1.06 1.09 1971 - 1981 1.17 0.76 1.14 1.15 1972 - 1982 1.02 0.77 0.93 0.97 1973 - 1983 0.66 0.34 0.40 0.49 1974 - 1984 0.67 0.35 0.37 0.48 1975 - 1985 0.99 0.73 0.87 1.01 1976 - 1986 1.04 0.92 1.00 1.04 1977 - 1987 1.52 1.31 1.54 1.49 1978 - 1988 1.59 1.42 1.33 1.39 1.34 1979 - 1989 1.30 1.27 1.38 1.31 1.09 1980 - 1990 1.11 1.07 1.21 1.08 0.87 1981 - 1991 0.57 0.15 0.47 0.13 1982 - 1992 0.25 0.03 0.13 0.08 1983 - 1993 0.78 0.27 0.52 0.47 1984 - 1994 0.59 0.33 0.51 0.48 1985 - 1995 0.76 0.54 0.74 0.01 1986 - 1996 0.80 0.51 0.69 -0.08 1987 - 1997 0.90 0.64 0.79 0.06 1988 - 1998 0.82 0.58 0.80 1989 - 1999 1.15 1.20 1990 - 2000 1.57 1.49 WP 02/14 | Measuring Economic Growth in New Zealand 31 Appendix D – New Zealand growth rates and growth rate rankings from alternative data sources Table D1 - New Zealand Growth Rates for Different Window Endpoints and Window Lengths based on PWT data Window endpoint Window length (years) 5 6 7 8 9 10 11 12 13 14 15 1958 2.80 1959 0.68 2.61 1960 3.10 2.75 4.10 1961 3.67 2.80 2.54 3.76 1962 3.19 3.24 2.56 2.36 3.46 1963 4.00 3.13 3.19 2.60 2.42 3.40 1964 4.36 3.91 3.18 3.22 2.69 2.52 3.41 1965 2.57 4.32 3.93 3.29 3.32 2.83 2.66 3.46 1966 2.50 2.30 3.84 3.57 3.04 3.08 2.66 2.52 3.27 1967 1.36 1.32 1.32 2.79 2.66 2.28 2.39 2.06 1.98 2.71 1968 0.61 0.98 1.00 1.04 2.38 2.30 1.99 2.11 1.83 1.77 2.47 1969 1.07 1.47 1.67 1.60 1.57 2.72 2.62 2.30 2.39 2.11 2.04 1970 0.85 1.39 1.68 1.83 1.75 1.71 2.74 2.65 2.35 2.43 2.17 1971 1.36 1.30 1.70 1.92 2.02 1.93 1.87 2.81 2.72 2.44 2.51 1972 2.85 1.61 1.52 1.84 2.02 2.10 2.01 1.96 2.81 2.73 2.47 1973 4.28 3.42 2.28 2.11 2.33 2.45 2.48 2.37 2.29 3.06 2.96 1974 3.99 4.29 3.54 2.53 2.36 2.53 2.61 2.63 2.52 2.43 3.14 1975 2.38 2.48 2.95 2.47 1.68 1.61 1.84 1.97 2.04 1.97 1.93 1976 1.87 2.15 2.27 2.71 2.30 1.62 1.56 1.77 1.90 1.97 1.91 1977 0.20 0.64 1.06 1.29 1.79 1.52 0.97 0.97 1.21 1.37 1.47 1978 -1.07 0.15 0.54 0.91 1.14 1.60 1.37 0.88 0.89 1.12 1.27 1979 -1.32 -0.39 0.56 0.85 1.15 1.33 1.74 1.51 1.05 1.04 1.25 1980 -0.27 -1.07 -0.30 0.52 0.78 1.06 1.23 1.61 1.41 0.99 0.99 1981 0.40 0.50 -0.29 0.28 0.95 1.14 1.36 1.49 1.82 1.62 1.21 1982 1.65 0.46 0.54 -0.16 0.33 0.93 1.10 1.31 1.43 1.74 1.57 1983 1.87 1.54 0.54 0.59 -0.04 0.40 0.93 1.09 1.28 1.40 1.69 1984 2.06 2.23 1.90 0.97 0.97 0.37 0.73 1.19 1.32 1.48 1.58 1985 2.02 1.72 1.91 1.66 0.86 0.87 0.33 0.66 1.10 1.22 1.38 1986 1.60 2.06 1.80 1.95 1.73 1.00 1.00 0.50 0.79 1.18 1.29 1987 1.43 1.31 1.75 1.55 1.72 1.54 0.90 0.91 0.45 0.72 1.09 1988 0.91 0.92 0.90 1.33 1.20 1.39 1.25 0.69 0.71 0.30 0.57 1989 0.56 1.13 1.11 1.07 1.44 1.31 1.47 1.34 0.81 0.83 0.43 1990 0.14 0.11 0.67 0.71 0.71 1.08 1.00 1.17 1.07 0.60 0.63 Max 4.36 4.32 4.10 3.76 3.46 3.40 3.41 3.46 3.27 3.06 3.14 WP 02/14 | Measuring Economic Growth in New Zealand 32 Table D2New Zealand’s growth rate ranking in the OECD for a number of different sub-periods based on PWT data Window endpoint Window length (years) 5 6 7 8 9 10 11 12 13 14 15 1958 15 1959 25 15 1960 11* 16 7* 1961 10* 14 17 11* 1962 13 12* 16 20 12* 1963 15 14 14 16 19 13 1964 15 15 18 14 19 19 15 1965 22 12* 15 16 12* 17 19 14 1966 22 23 14 17 17 15 18 21 15 1967 24 24 24 21 22 23 21 23 24 18 1968 25 24 24 24 24 23 24 24 24 24 21 1969 24 25 24 24 25 21 21 22 20 22 25 1970 25 25 25 25 25 25 21 22 21 21 23 1971 25 25 25 25 25 25 25 22 21 22 21 1972 22 25 25 25 25 25 25 25 22 22 22 1973 14 19 25 25 25 25 25 25 25 20 21 1974 14 11* 18 22 23 22 23 22 24 24 21 1975 15 19 19 21 23 24 24 24 23 23 25 1976 22 18 19 19 22 24 24 24 24 24 24 1977 24 24 24 24 21 24 25 25 25 25 25 1978 25 24 24 24 24 24 24 25 25 25 25 1979 25 25 24 24 24 24 24 24 25 25 25 1980 25 25 25 25 25 25 25 24 25 25 25 1981 23 23 25 25 23 24 22 22 19 25 25 1982 11* 22 23 25 24 22 23 21 21 20 23 1983 8* 12* 22 23 25 24 24 24 24 23 21 1984 5* 6* 10* 22 23 23 23 23 24 24 23 1985 9* 10* 11* 15 22 23 24 24 24 24 24 1986 13 9* 9* 10* 13 21 23 25 24 24 24 1987 21 20 14 16 15 17 24 24 25 25 24 1988 24 24 24 20 22 21 22 25 25 25 25 1989 24 24 24 24 23 23 21 22 25 25 25 1990 25 25 25 24 24 24 24 24 25 25 25 Best 5 6 7 10 12 13 15 14 15 18 21 Possible rankings range from 1 (highest growth rate for the period in the OECD) to 25 (lowest growth rate for the period in the OECD). * indicates that the growth rate ranking is sufficiently high to be categorised as being in the top half of the OECD. WP 02/14 | Measuring Economic Growth in New Zealand 33 Table D3 - New Zealand Growth Rates for Different Window Endpoints and Window Lengths based on Maddison 2001 data Window endpoint Window length 5 6 7 8 9 10 11 12 13 14 15 1955 0.83 1956 3.34 1.20 1957 3.08 2.87 1.11 1958 3.23 2.82 2.68 1.16 1959 1.95 3.51 3.11 2.95 1.57 1960 1.65 1.33 2.75 2.50 2.43 1.24 1961 1.72 1.94 1.63 2.84 2.60 2.53 1.44 1962 1.56 1.39 1.63 1.40 2.49 2.32 2.28 1.30 1963 2.09 1.99 1.79 1.95 1.71 2.66 2.49 2.43 1.52 1964 1.67 2.20 2.10 1.91 2.04 1.81 2.67 2.51 2.46 1.61 1965 2.93 2.14 2.53 2.41 2.20 2.29 2.06 2.82 2.66 2.61 1.80 1966 3.12 3.17 2.47 2.77 2.63 2.42 2.48 2.25 2.95 2.79 2.73 1967 1.94 1.58 1.84 1.39 1.78 1.75 1.64 1.76 1.61 2.30 2.19 1968 0.89 1.43 1.20 1.47 1.11 1.49 1.49 1.41 1.54 1.41 2.07 1969 2.19 2.29 2.56 2.21 2.34 1.93 2.20 2.14 2.02 2.09 1.94 1970 0.73 1.36 1.56 1.88 1.65 1.83 1.50 1.78 1.76 1.67 1.77 1971 0.56 1.20 1.68 1.81 2.07 1.84 1.99 1.67 1.92 1.89 1.80 1972 2.29 0.89 1.39 1.78 1.89 2.12 1.90 2.03 1.74 1.96 1.93 1973 3.52 2.75 1.48 1.84 2.14 2.20 2.38 2.16 2.26 1.97 2.16 1974 2.42 3.57 2.90 1.77 2.06 2.31 2.35 2.50 2.29 2.37 2.10 1975 2.40 1.53 2.64 2.17 1.25 1.57 1.83 1.91 2.08 1.92 2.02 1976 1.99 2.25 1.53 2.50 2.10 1.27 1.56 1.81 1.88 2.04 1.89 1977 0.43 0.78 1.18 0.68 1.64 1.36 0.68 0.99 1.26 1.37 1.56 1978 -0.49 0.42 0.72 1.08 0.65 1.51 1.27 0.66 0.94 1.20 1.30 1979 -0.91 -0.12 0.61 0.85 1.15 0.76 1.53 1.31 0.74 1.00 1.24 1980 -0.23 -0.67 -0.03 0.60 0.81 1.09 0.73 1.45 1.25 0.72 0.97 1981 0.36 0.55 0.05 0.52 1.02 1.17 1.39 1.04 1.68 1.48 0.97 1982 1.62 0.47 0.62 0.18 0.58 1.02 1.16 1.36 1.04 1.63 1.45 1983 1.82 1.57 0.60 0.71 0.31 0.66 1.06 1.18 1.36 1.06 1.61 1984 2.25 2.16 1.91 1.01 1.07 0.67 0.95 1.29 1.39 1.54 1.25 1985 2.21 1.93 1.90 1.71 0.94 0.99 0.64 0.90 1.22 1.31 1.46 1986 1.72 2.17 1.93 1.91 1.74 1.04 1.08 0.75 0.98 1.27 1.36 1987 1.43 1.36 1.80 1.64 1.65 1.52 0.91 0.96 0.66 0.88 1.16 1988 1.02 1.07 1.07 1.49 1.38 1.42 1.32 0.77 0.83 0.56 0.78 1989 0.30 0.90 0.97 0.98 1.36 1.27 1.32 1.24 0.74 0.79 0.55 1990 -0.07 -0.01 0.55 0.65 0.70 1.07 1.02 1.08 1.02 0.58 0.64 1991 -1.42 -0.86 -0.69 -0.12 0.05 0.15 0.54 0.53 0.63 0.61 0.22 1992 -1.37 -1.21 -0.76 -0.62 -0.12 0.03 0.12 0.48 0.48 0.57 0.56 1993 -0.47 -0.51 -0.50 -0.19 -0.13 0.27 0.37 0.43 0.73 0.72 0.79 1994 0.36 0.35 0.20 0.13 0.33 0.33 0.65 0.71 0.74 1.00 0.97 1995 1.14 0.70 0.64 0.48 0.38 0.54 0.52 0.80 0.84 0.86 1.09 1996 2.44 1.23 0.84 0.77 0.61 0.51 0.64 0.61 0.87 0.90 0.91 1997 2.65 2.18 1.19 0.85 0.79 0.64 0.54 0.66 0.64 0.87 0.90 1998 1.63 2.00 1.69 0.88 0.61 0.58 0.46 0.39 0.51 0.50 0.73 max 3.52 3.57 3.11 2.95 2.63 2.66 2.67 2.82 2.95 2.79 2.73 WP 02/14 | Measuring Economic Growth in New Zealand 34 Table D4New Zealand’s growth rate ranking in the OECD for a number of different sub-periods based on Maddison 2001 data Window endpoint Window length 5 6 7 8 9 10 11 12 13 14 15 1955 24 1956 13 23 1957 14 15 24 1958 11* 12* 13 24 1959 19 10* 10* 12* 24 1960 20 24 15 19 18 24 1961 19 19 20 16 18 17 23 1962 22 22 21 23 17 20 20 24 1963 21 20 22 22 24 17 19 20 24 1964 24 22 22 23 21 24 17 20 20 24 1965 22 23 22 22 22 20 24 17 18 18 24 1966 21 19 23 22 21 21 20 24 18 18 19 1967 24 24 24 24 24 24 24 24 24 22 24 1968 24 24 24 24 24 24 24 24 24 24 24 1969 23 24 23 24 23 24 24 24 24 24 24 1970 24 24 24 24 24 24 24 24 24 24 24 1971 24 24 24 24 24 24 24 24 24 24 24 1972 23 24 24 24 24 24 24 24 24 24 24 1973 14 23 24 24 24 24 24 24 24 24 24 1974 20 11* 20 24 24 23 24 23 23 23 24 1975 15 21 18 21 24 24 23 24 23 24 24 1976 23 18 23 20 22 24 24 23 23 23 23 1977 23 23 23 24 23 24 24 24 24 24 24 1978 23 23 23 23 24 23 24 24 24 24 24 1979 24 24 23 23 23 24 23 24 24 24 24 1980 24 24 24 24 24 24 24 24 24 24 24 1981 22 24 24 24 23 23 23 24 22 24 24 1982 12* 22 24 23 23 23 23 23 24 21 24 1983 9* 10 22 24 23 23 23 23 22 24 22 1984 6* 7* 9* 21 23 23 22 23 23 22 23 1985 8* 6* 8* 15 22 23 24 23 23 23 23 1986 14 10* 7* 11* 15 23 23 23 23 23 23 1987 19 20 15 15 17 18 24 24 23 23 23 1988 23 23 22 19 20 21 21 24 24 24 23 1989 23 23 23 23 21 22 23 23 24 24 24 1990 23 23 23 23 23 23 23 23 24 24 24 1991 23 24 24 24 23 23 23 23 24 24 24 1992 24 23 24 24 24 23 23 23 24 24 24 1993 21 24 23 24 24 24 23 23 23 23 24 1994 19 20 22 23 24 24 23 23 22 20 21 1995 15 17 19 23 22 22 23 23 23 22 21 1996 7* 15 16 20 22 22 22 23 22 22 22 1997 9* 9* 17 19 21 23 22 22 23 23 22 1998 18 13 13 22 23 23 24 23 24 24 23 best 6 6 7 11 15 17 17 17 18 18 19 Possible rankings range from 1 (highest growth rate for the period in the OECD) to 24 (lowest growth rate for the period in the OECD). * indicates that the growth rate ranking is sufficiently high to be categorised as being in the top half of the OECD. WP 02/14 | Measuring Economic Growth in New Zealand 35 Table D5 - New Zealand Growth Rates for Different Window Endpoints and Window Lengths based on Haugh’s Calibrated data Window endpoint Window length (years) 5 6 7 8 9 10 11 12 13 14 15 1983 1.64 1984 2.10 2.10 1985 2.13 1.84 1.88 1986 1.71 2.13 1.88 1.91 1987 1.71 1.37 1.78 1.60 1.66 1988 1.31 1.39 1.14 1.53 1.40 1.47 1989 0.39 1.06 1.17 0.98 1.34 1.24 1.32 1990 0.03 0.12 0.73 0.87 0.73 1.08 1.02 1.11 1991 -0.88 -0.38 -0.25 0.34 0.50 0.42 0.76 0.73 0.84 1992 -0.97 -0.86 -0.44 -0.31 0.21 0.37 0.31 0.63 0.61 0.72 1993 0.12 0.07 0.01 0.27 0.30 0.72 0.82 0.72 0.99 0.94 1.02 1994 0.94 0.75 0.61 0.49 0.67 0.66 1.00 1.07 0.96 1.19 1.14 1995 1.70 1.21 1.02 0.86 0.73 0.87 0.84 1.14 1.19 1.08 1.29 1996 2.47 1.66 1.24 1.07 0.92 0.80 0.92 0.89 1.16 1.21 1.10 1997 2.75 2.17 1.51 1.17 1.02 0.89 0.78 0.89 0.87 1.12 1.17 1998 1.63 2.23 1.80 1.27 0.99 0.88 0.78 0.68 0.79 0.78 1.02 1999 1.67 2.04 2.49 2.09 1.58 1.30 1.17 1.05 0.95 1.03 1.00 2000 1.43 1.67 2.04 2.49 2.09 1.58 1.30 1.17 1.05 0.95 1.03 Max 2.75 2.23 2.49 2.49 2.09 1.58 1.32 1.17 1.19 1.21 1.29