Since 1964, two key forces have fueled exceptionally fast GDP growth: the expansion of the labor supply, driven by rapid increases in population, and steady productivity gains. According to a report by the McKinsey Global Institute (MGI), the average annual GDP growth rate of 3.5% in the 19 member countries of the G-20 (not including the European Union) and Nigeria owes about 1.8 percentage points to labor and 1.7 points to productivity.
但如果我们还一切照旧，今后50年恐怕不太可能取得同样令人印象深刻的进步。1964年来，两股重要力量致令GDP增长异常迅速：由人口增长驱动的劳动力供应加大，以及稳步的生产率提高。根据麦肯锡全球研究院（MGI）即将发布的报告，G-20的19个成员国（不包括欧盟）和尼日利亚年均3.5%的GDP增长率中劳动力和生产率的比例各占1.8%和1.7%。