Journal Issue: Opportunity in America Volume 16 Number 2 Fall 2006
Contemporary and Past U.S. Mobility Rates
The best way to evaluate contemporary mobility is to compare it with the past. Strong evidence from several approaches shows that barriers to mobility weakened substantially for American men from the 1960s through the mid-1980s, thus increasing opportunity. Trends since that time are not yet clear, since the children born from the late 1980s onward have not yet entered the labor force. However, assuming there has been no change in mobility patterns, the rise in income inequality over the last few decades means that economic differences between families will persist for a longer time.
Barriers to mobility weakened substantially for American men during the 1960s; the intergenerational correlation in occupations fell from roughly 0.4 to 0.3 on the scale from 0 to 1.31 These trends continued for men until the mid-1980s; the correlation declined another 30 percent in ten years.32 Data sets for women are available only from the 1970s; they show that women's and men's intergenerational occupational mobility differed because the occupational distributions differed, but that the occupational mobility rate, adjusted for differences in distribution, did not differ for men and women. Trends for women resembled those for men as well.33
One major reason for the declining correlation between fathers' and sons' occupations was the climbing share of men with college degrees—occupational opportunity for college graduates is quite high, though of course the likelihood of college graduation is itself highly dependent on class background.34 State interventions on behalf of disadvantaged groups may also have contributed to the increased mobility.35
By itself, the declining effect of fathers' occupation should have increased overall occupational mobility in the United States between 1972 and 1985, but for these later years the increase in opportunity was counteracted by a slowdown in economic growth. (Conversely, the growth slowdown would have resulted in less social mobility in the United States were it not for the opposite trend in opportunity.) The combined effect of increased opportunity and slower growth kept overall mobility relatively high through 1985. Some evidence suggests that the trend toward greater opportunity slowed or reversed for men born after 1970, but data limits prevent firm conclusions at this time.36
Historically, over the course of the twentieth century economic growth produced more upward than downward movement. Mobility that results from a more open opportunity structure—a decreased advantage to upperstatus background—leads, however, to both downward and upward movement.37 So the changes in the American mobility pattern since the early 1970s have resulted in more downward mobility, especially for the offspring of the most privileged classes, and somewhat less upward mobility. Table 4 shows our calculations of the amount and direction of men's occupational mobility; that is, the share of men upwardly mobile, downwardly mobile, or immobile by year of birth. The earliest cohort (born in the 1930s) first entered the labor force in the 1950s and reached its top earning potential around 1980; the latest cohort (born in the 1970s) first entered the labor force in the 1990s and will reach its top earning potential around 2020. Almost half of the cohort born in the 1930s was upwardly mobile; only one-fourth of that cohort was downwardly mobile. Since then, fewer men have been upwardly mobile and more have been downwardly mobile. Among men born in the 1960s and 1970s, downward mobility is almost as prevalent as upward mobility. Immobility rose across cohorts from one-fourth to one-third.
Less is known about change over time in intergenerational income mobility. Some research has suggested a decline in the intergenerational elasticity among recent cohorts—indicating higher mobility—but the decline is not statistically significant (that is, it might appear by chance because of insufficient data), and using alternate data generates the conflicting finding that the elasticity may have increased.38 The most convincing finding is that there has been no change over the past century in intergenerational income mobility.39
Because the data for the analysis of trends over time in income mobility are limited, it is possible that trends did change but that data could not detect them. One way around that difficulty is to study change over time in how a set of family background indicators broader than father's earnings or family income may affect adult income. One such study used parent income, parent education, parent occupation, family race and ethnicity, family structure, number of siblings, and region to investigate how background affected economic outcomes over time. It found that the effect of family background on men's economic outcomes declined during the 1960s, then remained constant during the 1970s, 1980s, and 1990s. Although the effect of family background remained constant over those three decades, the economic gap between advantaged and disadvantaged men increased because economic inequality increased during this period. On the other hand, the effect of family background on women's outcomes declined between the 1970s and 1990s. Coupled with the increased economic inequality, this meant that the gaps in women's outcomes remained constant over the period.40
A yet broader approach investigates the joint impact of state residence, ancestry, and family income on men's economic outcomes and finds a down-up cycle. The intergenerational correlation between social origins and adult incomes was fairly constant from 1940 until 1960, fell substantially in 1970s (indicating increased mobility), and then returned to previous levels in the 1980s and 1990s. The intergenerational elasticity, on the other hand, declined between 1940 and 1980 but increased during the 1980s and 1990s. The measures are different because the elasticity is sensitive to income inequality, which followed the same trend over time—declining from 1940 to 1980 and then rising during the next two decades. The trends in the intergenerational correlation considered together with the elasticity suggest that income mobility was not abnormally low in the 1980s. But because economic inequality increased, the consequences of a historically normal degree of mobility were greater, and a greater share of the economic differences between families could persist for a longer time.41