Mobility for all: Representative intergenerational mobility estimates over the 20th century
What is this research about and why did you do it?
Intergenerational relative mobility — how tied an individual’s place in the income distribution is to their parents’ place in the income distribution while they were growing up — has long been an object of interest, especially in the US. However, evidence of long-term trends in intergenerational mobility is relatively limited and available estimates of mobility have typically excluded certain groups of the population (namely, women and Black Americans) due to data limitations. The contribution of this paper is providing the first estimates of long-run trends in intergenerational mobility for a representative sample of US-born individuals born between the1910s and the 1970s.
How did you answer this question?
We located and harmonized fifteen surveys that ask individuals their current family income as well as their race, father’s occupation, and region of birth/childhood. This method allows us to relate the family income reported by prime-age adults in these surveys to a measure of predicted family income during their childhood. Crucially, family income is a question that all respondents — even women who are notworking — can answer, allowing for the inclusion of women in the mobility estimates. Moreover, family income naturally reflects income gaps by race.
What did you find?
We have three main findings. First, we find a significant increase in intergenerational mobility for the 1910s–1940s birth cohorts. Both the intergenerational elasticity and the rank-rank correlation fell significantly during this period. Second, even though Black Americans are a relatively small share of the population, their convergence in incomes with white Americans accounts for roughly half of the rise in mobility. Finally, we show that excluding Black Americans— and in particular, Black women — from mobility estimates significantly overstates the level of mobility of any given cohort, while simultaneously understating the increase in mobility between the 1910s and 1940s cohorts.
Mobility patterns over the 20th century including under-represented groups.
What implications does this have for the study (research and teaching) of wealth concentration or economic inequality?
We show that the U.S. starts the 20th century further from the “American Dream” ideal of a mobile society but also improves more significantly when the full population is considered rather than only white men. Our results thus speak to the importance of using representative samples of the population for studying mobility. The increase in mobility that we find also suggests that mobility patterns are not set in stone, and that policy and institutions can play a role in changing mobility.
What are the next steps in your agenda?
We remain interested in better understanding the high upward mobility of certain groups (e.g., immigrants) as well as the role of institutions and policy (e.g., unions) in shaping the intergenerational transmission of advantage.
Citation and related resources
Jácome, E., Kuziemko, I., & Naidu, S. (2021). Mobility for all: Representative intergenerational mobility estimates over the 20th century (No. w29289). National Bureau of Economic Research. Journal of Political Economy.
