Family Income Dynamics 1970–2018: Putting the Pieces Together

This paper examines the driving forces of family income dynamics by developing a unified framework to estimate permanent and transitory variation in head earnings, spouse earnings, and transfer income, as well as permanent and transitory correlations between these income sources. A complete decomposition using the PSID 1970–2018 shows that transitory variation in head earnings alone accounts for more than half of the total family income inequality. Insurance against transitory shocks to head earnings comes primarily from transfer income rather than spouse earnings. Both permanent and transitory variations in spouse earnings have an equalizing effect on family income inequality.