In a Resolution Foundation report, Adam Corlett examines the “Elephant Curve.” The curve shows that between 1988 and 2008 income growth in the 70th to 95th percentile range of the world income distribution was much lower than for almost all other percentiles. Since the lower middle class of rich countries is situated around the 80th percentile of the distribution the Elephant curve has been interpreted as evidence for stagnating middle class incomes in the rich countries.
Corlett emphasizes that
- the country composition in 1988 and 2008 is not the same. Holding it constant the Elephant curve is less pronounced.
- “Population changes, rather than just income changes, have driven the income growth distribution in the elephant curve.” Holding the relative population size across countries constant the Elephant curve is less pronounced.
- There is lots of variation across developed economies. “[T]he weak figures for the mature economies as a whole are driven by Japan (reflecting in part its two ‘lost decades’ of growth post-bubble, but primarily due to likely flawed data) and by Eastern European states (with large falls in incomes following the collapse of the Soviet Union after 1988). Looking only at the remaining mature economies, far from stagnation we find average real income growth of 52 per cent with strong growth across the distribution, though slightly higher at the top. [But] there are great differences between these nations. US growth of 41 per cent was notably unequally shared, with low (but not zero) growth for poorer deciles meaning that the US comes closest to matching the stagnation and inequality narrative – despite international trade being much less important on a national level there than elsewhere [my emphasis]. But most people in most other rich countries experienced stronger growth.”