Portfolio choice for a resource-based sovereign wealth fund: An analysis of cash flows
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Mork, Knut Anton; Eap, Hanna Marisela; Haraldsen, Magnus Eskedal Article Portfolio choice for a resource-based sovereign wealth fund: An analysis of cash flows International Journal of Financial Studies Provided in Cooperation with: MDPI – Multidisciplinary Digital Publishing Institute, Basel Suggested Citation: Mork, Knut Anton; Eap, Hanna Marisela; Haraldsen, Magnus Eskedal (2020) : Portfolio choice for a resource-based sovereign wealth fund: An analysis of cash flows, International Journal of Financial Studies, ISSN 2227-7072, MDPI, Basel, Vol. 8, Iss. 1, pp. 1-20, https://doi.org/10.3390/ijfs8010014 This Version is available at: https://hdl.handle.net/10419/257681 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. Terms of use: Documents in EconStor may be saved and copied for your personal and scholarly purposes. You are not to copy documents for public or commercial purposes, to exhibit the documents publicly, to make them publicly available on the internet, or to distribute or otherwise use the documents in public. 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/
International Journal of Financial Studies Article Portfolio Choice for a Resource-Based Sovereign Wealth Fund: An Analysis of Cash Flows Knut Anton Mork 1,* , Hanna Marisela Eap 2and Magnus Eskedal Haraldsen 3 1Department of Economics, Norwegian University of Science and Technology, Klæbuveien 72, N-7491 Trondheim, Norway 2Ernst & Young AS, Dronning Eufemias gate 6, N-0191 Oslo, Norway; [email protected].com 3Danske Bank, Bryggetorget 4, N-0250 Oslo, Norway; [email protected] *Correspondence: [email protected]; Tel.: +47-9077-5756 Received: 22 December 2019; Accepted: 5 March 2020; Published: 7 March 2020 Abstract: We consider the portfolio choice of a government with a Sovereign Wealth Fund (SWF) when government revenues depend on exhaustible resources, such as oil and gas. The question is whether the SWF portfolio should underweight shares in the resource industry. Some studies have found that these share prices correlate more closely with the overall stock market than the resource price, which would seem to weaken the case for underweighting. However, equity price movements depend not only on changes in expectations of future cash flows, but also on time variation in discount factors. We analyze cash flows directly, rather than trying to disentangle these effects. We have collected cash-flow data for the companies in all of the major industries of the FTSE Global All Cap index, the basis for the strategic index of the Norwegian Government Pension Fund Global. Subsequently, we look at the correlations between each industry’s cash flow and the Norwegian government’s cash flow from oil and gas. We find a close, statistically significant, and persistent correlation for the oil and gas industry. The correlations for other industries are small and mostly insignificant. We believe that our findings can be used to support proposals for SWFs in countries with significant petroleum revenues to underweight shares in this industry. Keywords: concentration risk; cash flow correlation; Sovereign Wealth Fund JEL Classification: G11; G38 1. Introduction Elementary financial analysis warns against concentration risk. Diversification solves the problem because this kind of risk is idiosyncratic. Accordingly, financial investment portfolios should be diversified. However, many investors face risks outside their portfolios. Diversification for these investors should then consider the full spectrum of the risks that they face, financial risks, as well as background risks. When the background risks are positively (negatively) correlated with some of the financial assets, investment in these assets should then be underweighted (overweighted) relative to a financial portfolio that is perfectly diversified in the absence of background risks. Discussions of this issue on the literature include Bodie et al. (1992), Heaton and Lucas (2000), Viceira (2001), Benzoni et al. (2007), and Cochrane (2014). Sovereign wealth funds (SWF) are prime examples of financial portfolios that are held by investors with significant background risks. A quick look at the list of significant such SWFs (e.g., Baldwin 2012) reveals that a majority of the leading ones are owned by states with significant resource revenues. Of course, the reason is that the funds have been built up from these revenues. Although temporary Int. J. Financial Stud. 2020,8, 14; doi:10.3390/ijfs8010014 www.mdpi.com/journal/ijfs
Int. J. Financial Stud. 2020,8, 14 2 of 20 in a long perspective, the revenues usually last for decades. The continued inflow from resource extraction then raises concerns of concentration risks for the SWFs. The theoretical literature has been rather clear in its recommendation for the SWF to underweight or to avoid completely financial investments in the industry in question. The dynamic optimization analysis by van den Bremer et al. (2016) concluded that, as an example, the Norwegian Government Pension Fund Global (GPFG) should underweight or, indeed, take short positions in oil-industry shares for as long as the country’s government continues to receive rent-related revenues from its own oil industry. Henriksen and Kværner (2018) treat unextracted resources as a non-tradeable asset. Like van der Bremer et al., they use the Norwegian GPFG as their prime example. A report from the Norwegian Ministry of Finance (2016a) extends this argument by looking beyond the government’s assets to the nation’s total capital. Scherer (2019a,2019b), and Bodie and Bri è re (2013) are responsible for other contributions to this literature. Such theoretical arguments must be backed up by empirical facts to be useful for actual decision making. The correlation between financial assets and the asset in the ground should be reliably estimated. However, such estimation is far from trivial. The main problem is that the value of the resources in the ground is unobservable. Markets for such resources may be hard to organize, for example, because of problems of dynamic inconsistency, which can make potential buyers doubt assurances regarding future tax rates or regulations. Nevertheless, if a market is established, the market price might underestimate the social value of the resource, for the same reasons. Finally, because deposits differ widely in regard to geological conditions, the price of one deposit might be a poor indicator for the value of other deposits that have not yet been taken to the market. One might think that the market value of the extracted resource could work as a proxy for the asset value. It is, after all, the market price of a similar physical product as the one in the ground. In reality, it falls well short of the target, because it ignores the costs of extraction, which are not only significant, but also highly variable, depending on a number of geological, geographical, political, and other factors. Thus, it is hardly surprising that the Norwegian Ministry of Finance (2018) finds that the correlation between oil prices and oil-company stock prices is too low to warrant the underweighting of oil and gas shares in the GPFG. In fact, they find that the returns to oil and gas shares are more closely correlated with the overall equity market than with the price of oil. NBIM, Norges Bank Investment Management (2017a), which is the agency managing the investment of the GPFG, has looked closer at these correlations. They seek to separate stock price movements driven by changes in discount rates from those following from revisions of expectations of future cash flow while using the arguments of Campbell and Shiller (1988) and the method of Campbell (1991). They find empirical support for the claim that the close correlation between oil and gas stock returns and the overall stock market is mainly driven by variations in discount rates, which should be common across all industries. After separating out this effect, they find that the component reflecting revisions of cash-flow expectations is much more closely correlated with the world price of oil. While being highly suggestive, this contribution does not settle the issue. As the price of oil is a highly imperfect proxy for the value of oil in the ground, it compares apples and oranges. Furthermore, Campbell’s method is fraught with sampling as well as approximation errors from its reliance on linear approximations and key identifying assumptions. The main contribution of this paper is to circumvent these problems by instead looking directly at the correlation between oil and gas companies’ cash flows and the Norwegian government’s cash flow from oil and gas activities 1 . Furthermore, we compare this correlation with the corresponding correlations for the other major industries represented in the global stock market. By directly studying cash flows, we avoid the complications that are caused by time-varying discount factors. We also avoid the possible biases from linear approximations and special identifying assumption. On the other 1This idea was introduced to us by an op-ed article in a Norwegian business daily by Hoddevik (2018).
Int. J. Financial Stud. 2020,8, 14 3 of 20 hand, our analysis is subject to expectation errors by studying realized rather than expected future cash flows. If expectations are rational, this should not matter. Additionally, even if they are biased, our results should give a reliable guide to the relationship between the company asset prices and the imputed asset price of the government’s resource holding, only provided that the biases tend in the same direction. At the very least, we offer an alternative perspective on an issue for which a perfect method of analysis is simply not available. Pettit and Westerfield (1972) used cash flow data in an early extension of the single-factor capital asset market model (CAPM) by Sharpe (1964) and Lintner (1965). More recently, Cohen et al. (2009) argued that noise in high-frequency return data might distort tests of market efficiency and used cash-flow data to derive results to support their claim that the CAPM provides a satisfactory description of price-level data for buy-and-hold investors. In a similar vein, Campbell et al. (2010) compared cash-flow data to Campbell (1991) model in a study of growth stocks and value stocks. It is worth emphasizing that the concept of cash flow in these studies, including Campbell (1991), refers to dividends rather than the underlying company cash flows. The focus on dividends naturally makes sense from a stock investors point of view. However, fundamentally, it is the cash flow that is generated by the companies that form the basis for stock values. Furthermore, the Norwegian government’s petroleum revenues behave much more like company cash flows than dividends. Except for the small portion coming from Equinor (formerly Statoil) dividends, these revenues are roughly equally split between the special 78% tax rate on oil company profits and the cash flow from the government’s direct financial investment in oil and gas fields. Consequently, we find it natural to study the correlation between these revenues and the cash flow that is generated by listed companies in the respective sectors. A limitation of our study lies implicitly in the relatively young age of the Norwegian GPFG. Although its establishment was enacted by Parliament in 1990, the first deposit into the fund, corresponding to about USD 300 million, was not made until 1996; and, the first equity investments were not made until 1998. Furthermore, the fund’s current equity index, which is based on the FTSE Global All Cap index, was not launched until 2003, which forms the start of our sample. A look at the correlation between cash flows of oil and gas companies and the corresponding ones of the Norwegian government further back in time would nevertheless have been interesting. However, after serious consideration of this issue, we had to conclude that problems of data availability would make the results of any such effort uninformative.2 Using quarterly data could have increased the number of observations in our study, although not the length in calendar time. However, data for the Norwegian government’s net petroleum cash flow (GPCF) are only available in a meaningful way on the annual frequency. A quarterly breakdown would be dominated by irrelevant details concerning, for example, the timing of tax payments rather than the time profile of the actual earnings. This limits our sample to the 16 annual observations (15 first differences) between 2003 (2004) and 2018. These facts obviously limit the power of our statistical tests. On that background, we find it remarkable that we nevertheless find highly significant results. We find that the cash flows of oil and gas companies are very closely correlated with the Norwegian government’s cash flow from oil and gas activities. The corresponding correlations for the other industries are either much weaker or negative. Within the oil and gas industry, we find the strongest correlation for the subsector of integrated oil companies. We also find a significant, but much weaker, 2 As can be seen from Figure 1below, the government revenues were much smaller before the turn of the century and thus likely more influenced by idiosyncratic factors. Furthermore, oil and gas was not identified as a sector by the suppliers of equity indices until the mid-2000s. Indeed, some of the data for the early part of our sample had to be assembled manually. For data further back in time, we thus would have had to rely on just a few major companies, which would be likely to bias our results.
Int. J. Financial Stud. 2020,8, 14 4 of 20 correlation for the subsector of companies with only upstream operations in oil and gas. We find no significant correlations with the government’s cash flow for the other oil and gas subsectors. We believe these results to be supportive of the argument that the shares of integrated oil companies and upstream companies should be underweighted in the strategic indices of oil-rich countries’ SWFs, such as the Norwegian GPFG. Our results are only weakly supportive of the Norwegian government’s recent decision 3 to only underweight the shares of upstream companies. The explanation given for that decision was that the integrated oil and gas companies do more than resource extraction. However, we believe the Norwegian government ignored the dominant actors in the global upstream petroleum industry by excluding this subgroup. The organization of the rest of the paper is as follows. Section 2presents the GPFG. Section 3 presents the data for the Norwegian government’s petroleum cash flow, and Section 4displays the data for the cash flows of the global corporations that are relevant for the GPFG. Section 5presents the main results of our analysis. Section 6offers some robustness checks, and Section 7concludes. 2. The Government Pension Fund Global The GPFG is the Norwegian government’s vehicle for investing the extraordinary proceeds from the extraction of non-renewable petroleum resources and, thus, preserving this wealth for future generations. The government’s cash flow from oil and gas activity, to be further described in the next section, is the fund’s only source of deposits. By statute, all of this cash flow is deposited each year into the fund. Norges Bank Investment Management (NBIM) manages the fund, a division of the central bank. An Act of Parliament stipulates that the Government, in practice the Ministry of Finance, acts as the fund’s owner and formulates its investment strategy, subject to Parliamentary approval. A Fiscal Rule, which was adopted by Parliament in 2001 4 , allows for an annual draw from the fund corresponding to its expected real return. At the outset, the expected real rate of return was estimated as 4%. This rate was officially lowered to 3% in the 2018 budget after the ensuing experience of low riskless rates and a lengthy public debate. Although the rule allows for considerable flexibility, especially in response to the domestic business cycle, it has mainly been respected 5 . Even so, more than 15% of all government spending is currently financed from this source because of its fast growth to a total AMU exceeding USD 1 trillion. The fund is invested in equity, fixed income, and real estate in the global economy, with a certain overweight of European assets. Securities that are issued by Norwegian entities or in Norwegian kroner are excluded from the fund’s universe. Index replication governs most of the investments, although a small portion is actively managed 6 . The current strategic benchmark, issued by the Ministry of Finance, specifies an equity share of up to 70% and the rest in fixed income. 7 Investment in unlisted real estate can, at most, account for 7% of the total AUM. However, in index terms, such investments are considered part of the equity share and evaluated accordingly. Bloomberg provides the fund’s fixed-income benchmark index. It consists of the following three subindices: Global Treasury GDP, Global Inflation-linked, and Global Aggregate. It is made up of 70% government bonds in 21 different currencies, and 30% corporate bonds in seven different currencies. The government bonds are weighted according to each country’s GDP, and corporate bonds are weighted based on each company’s outstanding debt. The equity benchmark is based on the FTSE Global All Cap Index (GEISAC). It is market weighted and includes large, mid, and small cap stocks in both Developed and Emerging markets. The GEISAC index contains shares of around 8000 companies in 49 different countries. It was launched by 3Norwegian Ministry of Finance (2019). 4Norwegian Ministry of Finance (2001). 5Norwegian Ministry of Finance (2015). 6A further discussion can be found in Chambers et al. (2012). 7Norwegian Ministry of Finance (2016b).
Int. J. Financial Stud. 2020,8, 14 5 of 20 FTSE Russell in 2003 and was developed to be used for index tracking funds, derivatives, and as a performance benchmark for funds, such as the GPFG. The GPFG actually uses a modified version of the GEISAC, as stipulated by the Ministry of Finance. The greatest modification is the overweighting of European corporations and the exclusion of Norwegian ones. Shares by non-Norwegian European corporations are weighted at 2.5 times their actual market cap. For U.S. and Canadian corporations, the corresponding weights are unity; and, for the remaining developed and emerging markets, the weights are 1.5. Furthermore, the GPFG invests in the equity markets of twenty countries not included in the GEISAC index, including local Chinese equity (China A), Croatia, Saudi Arabia, and Morocco. Finally, some corporations are excluded for ethical or environmental reasons, such as tobacco, coal, and tar-sand companies. The GPFG is allowed to deviate from the strategic benchmark with a maximum deviation of an expected relative volatility of 1.25 percentage points in response to sudden market movements. The expected realized volatility is a measure of how much the return on the GPFG is expected to deviate from the benchmark index return in a normal year (Norges Bank Investment Management 2018). The NBIM is required to rebalance the equity allocation whenever the equity share significantly deviates from the strategic benchmark index. Our main interest in this paper is the fund’s investment in oil and gas companies. Table 1displays the overall industry allocation in the FTSE GEISAC index as well as the actual holdings of the GPFG at the end of 2018. The industry classification follows the FTSE Russel Industry Classification Benchmark (ICB). The Oil and Gas industry makes up 5.9% of the fund as well as the FTSE index. Although not an overly large sector when compared, e.g., to financials with a share of 23.7%, it is of special interest because investment in this sector might give rise to a concentration risk for the Norwegian economy. Table 1. The company count and industry weights for companies in each Industry Classification Benchmark (ICB) industry in the Government Pension Fund Global (GPFG) and FTSE Global All Cap Index (GEISAC), as well as their market value in the GPFG, as of Dec. 31, 2018. Sources: Norges Bank Investment Management (2017b) and FTSE Russell (2019). GPFG Equity Holdings FTSE Global All Cap Industry No. Industry Count NOK mn Weight % Count Weight % 0001 Oil and Gas 341 320,756 5.9 320 5.9 1000 Basic Materials 659 271,304 5.0 614 4.6 2000 Industrials 1966 708,762 12.9 1651 13.4 3000 Consumer Goods 1204 653,764 11.9 1009 11.0 4000 Health Care 723 626,847 11.4 544 11.2 5000 Consumer Services 1204 589,709 10.8 1008 11.5 6000 Telecommunications 130 163,344 3.0 129 2.8 7000 Utilities 252 155,333 2.8 286 3.3 8000 Financials 1859 1,299,103 23.7 1659 21.9 9000 Technology 809 689,838 12.6 644 14.4 Total 9158 5,478,760 100.0 7864 100.0 However, we should note that this industry includes companies that are not involved in petroleum extraction, such as pipeline companies and renewable-energy companies. For this reason, we also look at a further breakdown into subsectors as displayed in Table 2. As seen there, Integrated Oil and Gas dominates the Oil and Gas industry, with a share of almost two-thirds. This subsector contains the oil majors, such as Royal Dutch Shell, ExxonMobil, BP, and Chevron. These companies are involved in all parts of petroleum production, from exploration and drilling to refining and distribution. They may even be involved in other energy forms, such as renewables. However, we will also be interested in the second-largest subsector, Exploration and Production, which makes up one-fifth of the Oil and Gas industry. Here, we find upstream activities, like exploration, drilling, production, refining, and supply of oil and gas products (FTSE Russell 2019). Ex ante one might expect these activities to be most closely correlated with the activities generating the Norwegian government’s petroleum revenues.
Int. J. Financial Stud. 2020,8, 14 6 of 20 Table 2. The company count and industry weights for companies in the Oil and Gas subsectors in the GPFG and FTSE GEISAC, as well as their market value in the GPFG, as of 31 December 2018. Sources as in Table 1. GPFG Benchmark Index FTSE Global All Cap Subsector No. Industry Count NOK mn Wt % Count Weight % 0533 Exploration and Production 134 70,276 20.52 138 25.08 0537 Integrated Oil and Gas 61 223,066 65.13 62 57.88 0573 Oil Equipment and Services 73 20,227 5.91 78 6.98 0577 Pipelines 16 22,546 6.58 16 8.64 0583 Renew. Energy Equipment 23 6287 1.84 23 1.39 0587 Alternative Fuels 3 87 0.03 3 0.03 Total 310 342,489 100.00 320 100.00 The Pipelines subsector was established in 2006 when the industry classification benchmark ICB scheme was introduced. The subsectors Renewable Energy Equipment and Alternative Fuels were created in 2009. Thus, we do not have data for these subsectors from the earlier years. 3. The Norwegian Government’s Petroleum Cash Flow (GPCF) The Norwegian government started to collect revenue from oil activity on its continental shelf after the first discovery of oil in December of 1969. Figure 1shows the time series of these revenues in NOK 2019, converted to U.S. dollars. Although the first revenues started to trickle in shortly after oil was first discovered, they remained modest until a huge jump around the turn of the century. The annual revenues mainly stayed above USD 30 billion for our 2003–2018 sample. Int. J. Financial Stud. 2020, 8, x FOR PEER REVIEW 7 of 20 Dividends from this company have always only represented a small share of the government’s overall petroleum revenues, as shown in Figure 1. We converted each year’s revenues from Norwegian kroner into U.S. dollars, using the average exchange rate for that year, in order to make our data for the government’s petroleum revenues comparable to the cash flows of global corporations. This makes the data used in our analysis slightly different from the ones in Figure 1, which we find to be better suited for illustrative purposes. Figure 1. The Norwegian government’s net cash flow from petroleum activities. 4. Industry Operating Cash Flows One of the main contributions of this paper is the data that we have collected for the cash flows of companies in the global stock market, sorted by industry. For this purpose, we have combined data from several databases. We define operating cash flow as the sum of net revenue and non-cash expenses, net of changes in working capital. Operating cash flows can be reinvested in the company through fixed asset investments, used to reduce debt, or be directly paid out to owners as dividends. Although shareholders do not receive this cash flow, it forms the basis for how the companies are valued in the stock market. Company cash flows are reported in local currency, 41 individual currencies in all. We converted these amounts to U.S. dollars while using annual averages of daily exchange rates. We used exchange rates from the FRED database for the 23 currencies available there and the rest from Macrobond. Apart from this conversion, we analyze all of our cash flows in nominal terms. The cash-flow data for each company were taken from the S & P database Capital IQ, which we accessed via the Wharton Research Data Services. Each company was identified by means of CUSIP codes for North American companies and SEDOL codes for the rest. We obtained those codes from FTSE Russel for the companies that were included in the FTSE GEISAC index. This way, we obtained annual USD cash-flow data for 86,622 company-years out of the 121,581 data points from the FTSE, or 71.2% of the total. Table 3 shows the numbers of companies in our data set along with their aggregate weights in the GEISAC index. In 88 instances, we found multiple observations for a company’s operating cash flow within the same year. A number of Asian companies have reported annual figures for different time periods than January–December, such as March, February, or June. We then chose one of these for our annual observation. As an example, the figure that we use for operating cash flow for Keyence Corp in 2017 is the one reported in March 2018. For a few cases, the companies have switched from March to December as the end-of-period, resulting in two separate figures for the same calendar year. In these cases, we have used the figures that were reported at the same time of the year as in the following -10 0 10 20 30 40 50 60 Bn USD converted from NOK 2019 Taxes SDFI Statsoil/Equinor dividends Source: Norwegian Petroleum Figure 1. The Norwegian government’s net cash flow from petroleum activities. Figure 1also presents the breakdown of this revenue stream into its three main components: • Oil company taxes, mainly the special corporate income tax for this sector, as explained below. Environmental taxes, area fees, and other fees, are also included, though their contribution is minor. • The net cash flow from the government’s direct participation as a financial partner in oil field development and operation via the State Direct Financial Investment (SDFI) program. •Dividends from Equinor (formerly Statoil). For most of the years, the greatest share has come from oil-company taxes, mainly in the form of a special corporate income tax, as defined in the Petroleum Taxation Act of 1975. Oil companies do not
Int. J. Financial Stud. 2020,8, 14 7 of 20 pay for their production licenses. However, in addition to the normal corporate tax rate, currently 22%, profits from offshore operations are charged an additional tax that raises the marginal rate on such profits to 78%. This scheme is intended to mimic a rent tax, such that, in an approximate sense, the government receives the entire resource rent. A deductible amount is added to take care of the extensive margin, that is, to make sure that projects that are socially beneficial are also profitable after taxes. In addition, a reimbursement system for exploration costs was introduced in 2005, by which the government reimburses the company for 78% of exploration activities, even if the company has no taxable profits. The SDFI is the Norwegian government’s direct ownership shares in oil and gas fields, onshore facilities, and pipelines. This ownership share, which varies from field to field, is jointly determined with the awarding of production licenses. At the end of 2018, the SDFI portfolio consisted of shares in 38 fields, four of which are in the development phase, and 15 terminals and pipelines, representing approximately one third of the country’s total petroleum reserves. Via this route, the government only participates as a financial investor, contributing to investment expenditures as well as receiving its share of revenues. Since 2001, Petoro, a 100% government owned corporation, has acted as the government’s agent for these investments. Until 2001, the government also owned all of the shares of Statoil (now Equinor). The government share has been reduced to 67% since listing on the Oslo Stock Exchange that year. Dividends from this company have always only represented a small share of the government’s overall petroleum revenues, as shown in Figure 1. We converted each year’s revenues from Norwegian kroner into U.S. dollars, using the average exchange rate for that year, in order to make our data for the government’s petroleum revenues comparable to the cash flows of global corporations. This makes the data used in our analysis slightly different from the ones in Figure 1, which we find to be better suited for illustrative purposes. 4. Industry Operating Cash Flows One of the main contributions of this paper is the data that we have collected for the cash flows of companies in the global stock market, sorted by industry. For this purpose, we have combined data from several databases. We define operating cash flow as the sum of net revenue and non-cash expenses, net of changes in working capital. Operating cash flows can be reinvested in the company through fixed asset investments, used to reduce debt, or be directly paid out to owners as dividends. Although shareholders do not receive this cash flow, it forms the basis for how the companies are valued in the stock market. Company cash flows are reported in local currency, 41 individual currencies in all. We converted these amounts to U.S. dollars while using annual averages of daily exchange rates. We used exchange rates from the FRED database for the 23 currencies available there and the rest from Macrobond. Apart from this conversion, we analyze all of our cash flows in nominal terms. The cash-flow data for each company were taken from the S & P database Capital IQ, which we accessed via the Wharton Research Data Services. Each company was identified by means of CUSIP codes for North American companies and SEDOL codes for the rest. We obtained those codes from FTSE Russel for the companies that were included in the FTSE GEISAC index. This way, we obtained annual USD cash-flow data for 86,622 company-years out of the 121,581 data points from the FTSE, or 71.2% of the total. Table 3shows the numbers of companies in our data set along with their aggregate weights in the GEISAC index. In 88 instances, we found multiple observations for a company’s operating cash flow within the same year. A number of Asian companies have reported annual figures for different time periods than January–December, such as March, February, or June. We then chose one of these for our annual observation. As an example, the figure that we use for operating cash flow for Keyence Corp in 2017 is the one reported in March 2018. For a few cases, the companies have switched from March to December as the end-of-period, resulting in two separate figures for the same calendar year. In these cases, we
Int. J. Financial Stud. 2020,8, 14 8 of 20 have used the figures that were reported at the same time of the year as in the following years so as to obtain consistent time series. Typically, these companies switched from June to March reporting. Table 3. The number of companies for which we were able to find cash flow data, as well as their aggregate weights, in all industries and the Oil and Gas industry. The corresponding numbers for the companies in the FTSE GEISAC are shown for comparison. All Industries OIL and GAS Our Data GEISAC Our Data GEISAC Year Count Weight Count Weight Count Weight Count Weight 2003 4053 76.1% 6959 100% 130 6.0% 206 6.6% 2004 4806 79.1% 7595 100% 157 6.6% 231 7.3% 2005 5293 79.8% 8080 100% 199 7.7% 286 8.5% 2006 5436 80.5% 8116 100% 246 8.2% 334 8.8% 2007 5743 84.7% 7920 100% 268 9.8% 343 10.4% 2008 5735 87.7% 7756 100% 284 10.0% 366 10.6% 2009 5572 87.5% 7304 100% 316 9.8% 391 10.4% 2010 5615 87.4% 7301 100% 322 9.7% 393 10.4% 2011 5785 89.1% 7408 100% 340 10.5% 414 11.0% 2012 5469 86.6% 7197 100% 328 9.1% 395 9.7% 2013 5535 87.5% 7241 100% 327 8.5% 384 8.9% 2014 5838 87.8% 7580 100% 352 7.1% 418 7.3% 2015 6037 88.9% 7747 100% 335 5.7% 381 5.8% 2016 6088 89.8% 7725 100% 306 6.8% 336 7.0% 2017 6231 90.0% 7788 100% 303 5.8% 319 6.0% 2018 3386 68.5% 7864 100% 219 5.2% 320 5.9% Average 5414 84.4% 7599 100% 277 7.9% 345 8.4% The importance of an industry’s cash flow to the GPFG depends on that industry’s weight in the fund’s index. We weighted each company’s cash flow by its industry’s weight in the GPFG’s index to capture this importance, and to correct for the missing data, the extent of which varies by industry, according to the formula Weighted Cjt = Nj X i=1 wjtCijt, where Cijt is the cash flow of company i in industry j for year t , Nj is the number of companies within industry j , and wjt is the index weight of industry j at time t . The industry weights, which vary slightly from year to year, are shown in Table 4. Table 4. The weights of ICB industries in the Government Pension Fund Global over time. Source: Norges Bank Investment Management (2019). Year Oil and Gas Basic Mat. Industrials Cons. Goods Health Care Cons. Serv- Telecom Utilities Financials Technology 2003 7.9% 4.8% 10.3% 10.8% 10.6% 11.2% 6.9% 3.0% 25.3% 9.2% 2004 8.3% 4.6% 10.8% 9.8% 9.9% 11.6% 7.0% 3.4% 26.7% 7.9% 2005 9.4% 5.5% 10.8% 9.9% 9.6% 10.3% 5.1% 3.7% 27.1% 8.7% 2006 8.0% 5.6% 11.1% 10.7% 8.0% 9.6% 4.7% 4.8% 29.3% 8.1% 2007 10.1% 7.5% 12.4% 11.8% 7.7% 8.7% 5.3% 5.2% 23.2% 8.3% 2008 11.0% 6.3% 11.4% 12.1% 10.3% 8.6% 6.1% 6.0% 21.1% 7.1% 2009 10.8% 8.0% 12.0% 11.3% 8.6% 8.3% 5.1% 4.8% 22.8% 8.3% 2010 10.8% 9.1% 13.7% 11.6% 7.7% 8.5% 4.5% 4.7% 21.5% 7.9% 2011 11.6% 7.8% 13.1% 12.7% 9.5% 9.0% 4.4% 4.3% 19.8% 7.9% 2012 9.9% 7.5% 13.1% 13.6% 8.7% 9.3% 3.9% 3.8% 23.0% 7.3% 2013 8.3% 6.3% 14.3% 13.9% 8.7% 10.2% 3.8% 3.4% 23.6% 7.4% 2014 6.9% 5.7% 13.6% 13.8% 9.6% 10.4% 3.3% 3.7% 24.5% 8.4% 2015 5.4% 5.1% 13.5% 14.4% 10.7% 10.9% 3.4% 3.2% 24.5% 9.0% 2016 6.4% 5.6% 14.0% 13.6% 10.1% 10.2% 3.2% 3.1% 24.3% 9.4% 2017 5.6% 6.0% 14.3% 13.5% 9.8% 10.1% 2.8% 2.6% 24.3% 11.1% 2018 5.9% 5.0% 12.9% 11.9% 11.4% 10.8% 3.0% 2.8% 23.7% 12.6% Our data set has two main weaknesses beyond the limited number of years for which we have observations.
Int. J. Financial Stud. 2020,8, 14 15 of 20 Int. J. Financial Stud. 2020, 8, x FOR PEER REVIEW 15 of 20 Figure 3. Rolling estimates of correlations. 6.4. Cross Correlograms Our final robustness check concerns correlations at various leads and lags. Specifically, for each of the major industries, we computed correlations for the industry cash flow at time 𝑡+𝑘 with the Norwegian government’s petroleum cash flow at time 𝑡. The results are presented as a cross correlogram for each industry. Thus, the column, labeled “–3”, denotes the correlation between the government’s petroleum cash flow and the cash flow of the industry in question three years earlier, and so on. In the results presented in Figure 4, one item stands out, namely, a correlation of 0.8 between the government’s cash flow and the cash flow of the Basic Materials industry one year earlier. We interpret this finding as supportive of the notion that fossil fuels often move together with other materials. We note it as a possible argument for underweighting the shares in the Basic Materials industry as well as Oil and Gas. However, given the one-year lag, we recognize that this argument is much weaker than for Oil and Gas. We also find correlations above 0.6 for utilities, but at two-year leads and lags. -1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0 04 - 10 05 - 11 06 - 12 07 - 13 08 - 14 09 - 15 10 - 16 11 - 17 12 - 18 Oil & Gas Basic Materials Industrials Consumer Goods Health Care Consumer Services Telecommunications Utilities Financials Technology Figure 3. Rolling estimates of correlations. 6.4. Cross Correlograms Our final robustness check concerns correlations at various leads and lags. Specifically, for each of the major industries, we computed correlations for the industry cash flow at time t+k with the Norwegian government’s petroleum cash flow at time t . The results are presented as a cross correlogram for each industry. Thus, the column, labeled “–3”, denotes the correlation between the government’s petroleum cash flow and the cash flow of the industry in question three years earlier, and so on. In the results presented in Figure 4, one item stands out, namely, a correlation of 0.8 between the government’s cash flow and the cash flow of the Basic Materials industry one year earlier. We interpret this finding as supportive of the notion that fossil fuels often move together with other materials. We note it as a possible argument for underweighting the shares in the Basic Materials industry as well as Oil and Gas. However, given the one-year lag, we recognize that this argument is much weaker than for Oil and Gas. We also find correlations above 0.6 for utilities, but at two-year leads and lags. Furthermore, we constructed similar cross correlograms for the three subsectors of the Oil and Gas industry, for which we have data for the entire sample period. Figure 5shows the results. There, we note the correlations of around 0.5 for Oil Equipment and Services at both the one-year lag and the one-year lead. These modestly large correlations may perhaps reflect the leads and lags in the industry itself, in that higher investment might presage higher government petroleum revenues and also that high government revenues (due, e.g., to higher prices) may signal higher future investments in the industry. However, the lack of contemporaneous correlation makes such a conclusion tenuous.
Int. J. Financial Stud. 2020,8, 14 16 of 20 Int. J. Financial Stud. 2020, 8, x FOR PEER REVIEW 16 of 20 Figure 4. Cross correlograms for leads and lags of industry cash flows. Furthermore, we constructed similar cross correlograms for the three subsectors of the Oil and Gas industry, for which we have data for the entire sample period. Figure 5 shows the results. There, we note the correlations of around 0.5 for Oil Equipment and Services at both the one-year lag and the one-year lead. These modestly large correlations may perhaps reflect the leads and lags in the industry itself, in that higher investment might presage higher government petroleum revenues and also that high government revenues (due, e.g., to higher prices) may signal higher future investments in the industry. However, the lack of contemporaneous correlation makes such a conclusion tenuous. -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Health Care -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Consumer Services -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Telecommunications -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3-2-10123 Utilities -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Industrials -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Consumer Goods -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Energy -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Basic Materials -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Exploration & Production -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3-2-10123 Integrated Oil & Gas -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3-2-10123 Oil Equipment & Services Figure 4. Cross correlograms for leads and lags of industry cash flows. Int. J. Financial Stud. 2020, 8, x FOR PEER REVIEW 16 of 20 Figure 4. Cross correlograms for leads and lags of industry cash flows. Furthermore, we constructed similar cross correlograms for the three subsectors of the Oil and Gas industry, for which we have data for the entire sample period. Figure 5 shows the results. There, we note the correlations of around 0.5 for Oil Equipment and Services at both the one-year lag and the one-year lead. These modestly large correlations may perhaps reflect the leads and lags in the industry itself, in that higher investment might presage higher government petroleum revenues and also that high government revenues (due, e.g., to higher prices) may signal higher future investments in the industry. However, the lack of contemporaneous correlation makes such a conclusion tenuous. -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Health Care -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Consumer Services -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Telecommunications -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3-2-10123 Utilities -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Industrials -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Consumer Goods -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Energy -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Basic Materials -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3 -2 -1 0 1 2 3 Exploration & Production -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3-2-10123 Integrated Oil & Gas -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -3-2-10123 Oil Equipment & Services Figure 5. Cross correlograms for leads and lags of Oil and Gas subsector cash flows.
Int. J. Financial Stud. 2020,8, 14 17 of 20 7. Conclusions Ultimately, equities are all about cash flows, the right to current and future cash flows, with future cash flows being discounted at stochastic rates that may change over time. Thus, cash flows form the basis for equity prices. Investors, in turn, choose portfolios that are appropriately diversified, so as to minimize the risk given the rate of return. However, they also need to keep an eye on background risks to make sure that correlations between those risks and financial risks don’t introduce unwanted concentration risks. Assessing such risks often runs into problems regarding how to compare the different risks. This paper studies this problem for a government that regularly receives special revenues from the extraction of a non-renewable natural resource and, at the same time, holds a portfolio of equities that includes shares in the companies of that same industry. The comparison problem arises because the estimation of the correlation between asset prices in that industry and the government’s value of the assets in the ground is infeasible because the value of the asset in the ground is unobservable. Some previous attempts to solve this problem have used the market price of the extracted resource as a proxy for the value of the asset in the ground. Others have sought to econometrically distinguish those movements in the equity prices for companies in the ground that are driven by changing expectations of cash flows from those that are due to time variations in discount factors. In this paper, we have bypassed this problem by instead directly comparing the government’s cash flow from the resource to the aggregated cash flows of the global companies in the resource industry in question. In particular, we have studied the correlations between the Norwegian government’s petroleum cash flow with the cash flows of companies in the global oil and gas industry, as well as with companies in other major industries. We find a uniquely high correlation between the government’s cash flow and the cash flow of companies in the global oil and gas industry. This correlation is unmatched, by a wide margin, by any other industry. Within oil and gas, we find the greatest correlations for the subsector containing integrated oil and gas companies and a somewhat weaker, yet significant, correlation for the subsector of oil and gas companies with upstream companies only. For the Norwegian Government Pension Fund Global, we believe that our findings strongly support the underweighting, perhaps even shorting, of oil and gas shares in particular, and particular for the large, integrated oil and gas companies. However, we believe that our methodology should be relevant to other governments as well whose revenues come from other kinds of natural resources, such as coal, iron ore, copper, bauxite, lithium, or—in the future—wind or sunshine. Further investigation of such cases would be an interesting extension of our work. Author Contributions: Conceptualization, K.A.M.; methodology, K.A.M.; software, H.M.E. and M.E.H.; validation, K.A.M.; formal analysis, H.M.E. and M.E.H.; investigation, H.M.E. and M.E.H.; resources, H.M.E. and M.E.H.; data curation, H.M.E. and M.E.H.; writing—original draft preparation, H.M.E. and M.E.H.; writing—review and editing, K.A.M.; visualization, K.A.M.; supervision, K.A.M.; project administration, K.A.M.; funding acquisition, K.A.M. All authors have read and agreed to the published version of the manuscript. Funding: K.A.M. acknowledges financial assistance from Finansmarkedsfondet, the financial markets research fund under The Research Council of Norway, Project no. 294398. Acknowledgments: This paper is the revised version of a MSc thesis written at NTNU by H.M.E. and M.E.H. under K.A.M.’s supervision. The authors are indebted to two anonymous referees and to Halvor Hoddevik for suggesting the topic and for help with the data collection as well as the analytical methods. Conflicts of Interest: The authors declare no conflict of interest.
Int. J. Financial Stud. 2020,8, 14 18 of 20 Appendix A Table A1. Correlations between the operating cash flow of each industry and the GPCF. Industry cash flow weighted with FTSE GEISAC industry weights. All correlations on first-difference data 2004–2018. Industry Correlation t-Value Oil and Gas 0.80 4.81 *** Basic Materials −0.11 −0.40 Industrials −0.30 −1.12 Consumer Goods −0.52 −2.20 * Health Care 0.13 0.48 Consumer Services −0.04 −0.14 Telecommunications 0.02 0.05 Utilities 0.35 1.33 Financials −0.15 −0.54 Technology −0.21 −0.76 All industries −0.12 −0.43 All industries ex Oil and Gas −0.25 −0.93 *** p<0.01, * p<0.1. Table A2. Correlations between the operating cash flow of each industry and the GPCF. Each company’s cash flow weighted individually with the weights in the FTSE GAISAC index, scaled to correct for missing observations. Industry Correlation t-Value Oil and Gas 0.88 6.82 **** Basic Materials 0.10 0.38 Industrials 0.29 1.11 Consumer Goods −0.20 −0.75 Health Care 0.44 1.77 Consumer Services 0.36 1.38 Telecommunications 0.25 0.91 Utilities 0.38 1.50 Financials −0.33 −1.28 Technology −0.06 −0.23 All industries 0.26 0.96 All industries ex Oil and Gas −0.17 −0.63 **** p<0.0001. Table A3. Correlations between the government’s petroleum cash flow and the unweighted operating cash flows of each ICB industry. Industry Correlation t-Value Oil and Gas 0.80 4.86 *** Basic Materials 0.20 0.72 Industrials −0.27 −1.00 Consumer Goods −0.61 −2.80 ** Health Care −0.27 −1.01 Consumer Services −0.14 −0.52 Telecommunications −0.46 −1.87 * Utilities −0.02 −0.07 Financials −0.01 −0.03 Technology −0.13 −0.46 All industries −0.04 −0.15 All industries ex Oil and Gas −0.21 −0.79 *** p<0.01, ** p<0.05, * p<0.1.
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