We were all lucky to be born at the right time. Over the past 50 years, world GDP growth has been averaging 3.6 per cent, driven by employment increases and productivity improvements in roughly equal proportions. An exhaustive and important study by the McKinsey Global Institute concludes that over the next 50 years, population growth will decline to 0.3 per cent annually. If productivity continues to contribute 1.8 per cent, overall growth will decline to 2.1 per cent, a rate 40 per cent less than during the past half-century. The implications of this slowdown on global changes in the standard of living and investment opportunities could be enormous.



The developing world can improve its growth potential by adopting operational practices and technology used by the advanced countries (that is, by catching up), but the US, Europe and Japan will continue to depend heavily on innovation to approach anything like their historical rate of growth. Those subscribing to Mohamed El-Erian's concept of "the new normal" or Harvard Professor Alvin Hansen's "secular stagnation" may turn out to be right, but for reasons somewhat different than they originally thought. I have been worried about a lack of demand causing a slowdown in growth. I had not thought that the main problem might be that there aren't enough people out there to do the buying.



The global economy grew sixfold in the past 50 years. Taking into account the projections above, it is only expected to grow threefold in the next 50. Population growth rose because of high fertility rates, declining infant mortality and longer life expectancy. Also, the number of people of working age (15-64) grew from 58 per cent of the population in 1964 to 68 per cent last year. The productivity improvement resulted from a shift from agriculture to manufacturing and services. Technology obviously played an important role. According to the McKinsey study, the average world employee today generates 2.4 times the output of his counterpart in 1964. Because Europe and the US were relatively efficient in 1964, their productivity rose only 1.5 per cent and 1.9 per cent annually respectively, while South Korea and Japan rose 4.6 per cent and 2.8 per cent respectively. As expected, China's productivity grew at 5.7 per cent annually, but Mexico and Saudi Arabia experienced less than 1 per cent annual productivity growth. The study notes that the productivity gap between the developed and the developing economies remains wide, at almost five times, providing a big opportunity for emerging markets.



The big change in the future will be the slow growth in population. Fertility rates are declining, and the average age of the population in Europe, China and Japan is rising. China's peak employment is expected to occur in 2024. The working age population in the G19 countries plus Nigeria is expected to decline from 68 per cent to 61 per cent over the next 50 years. By 2064, India's employment could expand by 54 per cent, while China's could shrink by 20 per cent. The number of employees in the US is expected to continue to rise, but at a slower rate than in the past. By employing more women and encouraging people to stay at their jobs beyond age 64, the expected 0.3 per cent rate of working population growth could double, but that would still be well below the pace of the last 50 years.



The McKinsey estimates of annual population growth seem low to me, but the concept of slower growth in the number of people in the world appears sound. A somewhat less pessimistic study of population growth was prepared for me by Dick Hokenson, the demographic analyst at Evercore ISI. He points out that the G19 plus Nigeria universe includes Germany, Russia, Japan, China and South Korea, all of which will experience overall declines in their populations and labour forces over the next 50 years. If you look at the entire world, the decline in growth is still significant but goes only from 1.8 per cent to about 0.5 per cent. By last year, world population had risen to 6.4 billion from 2.9 billion in 1964. Some put it higher. I have seen estimates of 9 billion in 2064, implying a population growth roughly half that of the past 50 years.



The McKinsey study states that productivity improvement could compensate for the slower rise in population, but over the next 50 years it would have to be 80 per cent faster than the already rapid growth of the past half century. Given all the technology breakthroughs of the past few decades, including the cell phone, the personal computer and the internet, that accelerated rate seems unlikely to me. The study concludes that, worldwide, as much as three-quarters of productivity growth will come from a broader adoption of best practices. These opportunities exist in certain geographic areas and include using more effective retail formats, increasing the scale and capacity of automobile assembly, improving operational efficiency in health care and reducing waste in food service. The developing world would be the greatest beneficiary of the adoption of best practices, which would account for 82 per cent of its estimated productivity improvement. In contrast, the developed world would realise only 55 per cent of its productivity improvement from the implementation of best practices. The rest would come from "pushing the frontier" or innovation.



While one usually thinks adopting best practices applies mainly to manufacturing and services, agriculture continues to provide considerable opportunities. On the innovative side, the study argues that the technological advances of the last 50 years will continue to have a significant impact on productivity. Profit margins for the Standard & Poor's 500 are now above 10 per cent, having risen sharply since the end of the recession in 2009. Historically they have never been much higher than that. Margins have improved as a result of employing technology and keeping labor costs low. Capital equipment has been used to replace labor and the vast pool of people looking for a job has enabled companies to hire workers without significant increases in wages. As a result, unit labour costs have been rising very slowly. Given that a Ned Davis Research study of non-farm productivity year-by-year over the past 65 years shows increases of 2.3 per cent a year, the likelihood that this statistic could rise significantly seems remote. The most recent quarterly gain was less than 1 per cent. Over the past 20 years there have been several quarters where productivity improvements have exceeded 5 per cent, but about 2 per cent is the best the US economy has been able to achieve since the recovery began in 2009.

Ten enablers of growth

Productivity growth has actually slowed in the developed economies, from 3.2 per cent in the 1964-74 period to 0.8 per cent during 2004-14. In the emerging markets, however, it has more than doubled from 2.6 per cent during 1964-74 to 5.6 per cent in 2004-14. In 1964, the differential between the dollar output per employee in the developed economies versus the developing economies (on a purchasing power parity basis) was $US32,000. Even though productivity has improved faster in the developing economies, the differential last year was dramatically higher at $US73,000.



In the recent past, companies were clearly willing to spend a significant part of their operating cash flow on capital equipment. They were not, however, building new plants. Instead, they were buying hardware, software and robotics to enable them to increase the output of goods and services using fewer workers. While the net income per employee has increased in each cycle, capital spending as a percentage of operating cash flow has actually declined in the past three cycles. I still expect capital spending to be one of the positives for the economy this year, but this factor may be less robust than I originally thought.



We will need to focus on the implications of only modest population growth on economic expansion. The McKinsey report lists 10 enablers of growth. They include improving the regulatory environment to encourage innovation, focusing on matching skills to employment opportunities in education, removing barriers to competition in service industries, improving cross border activity through trade pacts, encouraging more women to take part in the workplace, asking productive employees to work beyond the normal retirement age, improving infrastructure and stepping up research and development spending. Every one of these would contribute to growth but, since both government policy and established practices are hard to change, any positive shifts are likely to be seen only over a long period.



For investors, this means that profit margins are likely to be under pressure if the boost from productivity improvements diminishes. It also means that revenue increases may be modest as the population grows more slowly. Because these factors will have a negative impact on earnings growth, companies will focus more on financial engineering, including share buybacks and leverage, as well as mergers and acquisitions, to increase earnings. A premium will be paid for innovation, and investors will seek out the industries and companies that can provide it.



For the largest countries, the decline in the growth rate is projected to be serious, says the McKinsey study. The US drops from a rate of 2.9 per cent in the past 50 years to 1.9 per cent in the next 50, Germany from 2.2 per cent to 1 per cent, Japan from 3.3 per cent to 2.1 per cent and the United Kingdom from 2.2 per cent to 2.0 per cent. In the emerging markets, China moderates from 7.5 per cent to 5.3 per cent, India from 5.1 per cent to 3.0 per cent, Brazil from 4.0 per cent to 1.6 per cent, Mexico from 3.7 per cent to 1.3 per cent and Russia from 1.6 per cent to 0.6 per cent. In my view, all of these countries are counting on achieving better growth (or at least the same rate of growth) in the future than they have seen in the past. Every government is promising an improved standard of living for its citizens, rather than the reduction implied by declining growth. A big effort by the public and private sectors will be required to reverse this trend.



The emerging markets have accounted for the big change in world employment. Based on the McKinsey report, China had 452 million more people employed last year than in 1964. India had 335 million more and even the US had 75 million more people working in 2014 than in 1964. Looking forward, India is expected to add the most employees over the next 50 years, 255 million, followed by Nigeria at 153 million. The US will hold its own by adding 38 million. China will be the big loser with 152 million fewer employees.



One way to create more jobs is to reduce the work week. Presumably, that also improves the quality of life. Shortening the work week has been going on around the world for the past 50 years. South Korea had the longest work week at 42 hours in 2012, but even that was down two hours from 1964, says the McKinsey study. Other notable changes were Turkey, down to 36 hours from 45 in 1964, Italy down to 34 from 45, France down to 28 from 41, the United Kingdom, down to 32 from 42 and Germany down to 27 from 40. In the US, the reduction was only down three hours to 33 from 36.



Investors tend to assess the outlook primarily on a short-term basis. Right now, the focus is the effect of lower oil prices and the strong dollar on 2015 earnings. Some investors may also be concerned about the implications of geopolitical issues including Greece possibly leaving the European Union, Russia's expansionary policies or the Iran nuclear agreement. The purpose of looking at growth projections for the next 50 years is to consider their impact on other important factors that could have a negative influence on earnings. If population growth slows as projected, productivity must improve strongly to maintain worldwide growth at anything like the rate of the past 50 years. That seems like a difficult hurdle to me. As investors, we would see the manifestations of this trend in a slower rate of earnings improvement and more modest rates of equity market appreciation. The fact that 2015 S & P 500 earnings are expected to increase by only a small amount may be the dawn of this condition, obscured by the short-term factors of the oil price drop and the strong dollar.



I have been doing strategy analysis for a long time. I remember back in the 1970s, there was an alarming report by something called the Club of Rome (CoR), a group of respected macro-economic thinkers of that era. The first report of the CoR was called "The Limits to Growth", published in 1972, and it purportedly sold an incredible 30 million copies in 37 languages. The study focused on the environment and the links among energy, food and population over the coming 100 years. "The Limits to Growth" was very controversial and widely discussed, but the recommendations for economic self-denial were largely ignored and you rarely hear much about the Club of Rome today (but it still exists). Although the conclusions of the report were directionally right, its tone was apocalyptic and the consensus today is that the analysis was incorrect.



The equity markets in the early 1970s were very unstable because of near-term economic factors, and the CoR report unsettled them further. As events played out, the financial markets drifted to a long-term low in 1982 and then began one of the greatest periods of positive performance in history. Perhaps the McKinsey Global Institute's concern about future growth rates declining because of slow increases in population will be similar to the CoR phenomenon, and the trend will develop differently than the report suggests. Most of us worry that there are now too many people in the world for the number of productive jobs, and that this mismatch causes many to live in desperate circumstances. A proper understanding of the actual trajectory of population growth and productivity around the world will be critical to determining an effective investment strategy.



Byron Wien is Vice Chairman of Blackstone Advisory Partners LP where he acts as a senior adviser to both the Firm and its clients in analyzing economic, social and political trends to assess the direction of financial markets and thus help guide investment and strategic decisions.

By 2064, India's employment could expand by 54 per cent.

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