At least five large studies in recent years have found the United States to be less mobile than comparable nations. A project led by Markus Jantti, an economist at a Swedish university, found that 42 percent of American men raised in the bottom fifth of incomes stay there as adults. That shows a level of persistent disadvantage much higher than in Denmark (25 percent) and Britain (30 percent) — a country famous for its class constraints.
Meanwhile, just 8 percent of American men at the bottom rose to the top fifth. That compares with 12 percent of the British and 14 percent of the Danes.
Despite frequent references to the United States as a classless society, about 62 percent of Americans (male and female) raised in the top fifth of incomes stay in the top two-fifths, according to research by the Economic Mobility Project of the Pew Charitable Trusts. Similarly, 65 percent born in the bottom fifth stay in the bottom two-fifths.
By emphasizing the influence of family background, the studies not only challenge American identity but speak to the debate about inequality. While liberals often complain that the United States has unusually large income gaps, many conservatives have argued that the system is fair because mobility is especially high, too: everyone can climb the ladder. Now the evidence suggests that America is not only less equal, but also less mobile.