Schoeni, Robert F., and Kathleen McGarry. 2000. "Social Security, Economic Growth and the Rise of the Elderly Widows' Independence in the Twentieth Century." Demography, 37(2): 221-36.
The percentage of elderly widows living alone rose from 18% in 1940 to 62% in 1990, while the percentage living with adult children declined from 59% to 20%. This study finds that income growth, particularly increased Social Security benefits, was the single most important determinant of living arrangements, accounting for nearly one-half of the increase in independent living. Unlike researchers in earlier studies, no evidence is found that the effect of income became stronger over the period. Changes in age, race, immigrant status, schooling and completed fertility explain a relatively small share of the changes in living arrangements.