Incidence of four-generation family lineages: is timing of fertility or mortality a better explanation?

OBJECTIVES This article estimates the percentage of lineages that include four or more generations for a sample of the U.S. population and explores how social status and race are related to lineage depth. METHODS We assembled data from Waves 1 and 2 of the National Survey of Families and Households in order to estimate the proportion of adults in four or more generations for the Wave 2 sample (1992-1994). When necessary, we used various decision rules to overcome an absence of information about specific generations. We examine relationships between lineage depth and sociodemographic variables by using logistic regressions. RESULTS The data show that 32% of the respondents were in lineages comprising four or more generations. Blacks and individuals of lower social class were more likely to be in four-generation lineages, especially shorter-gapped lineages. Whites and individuals of higher social class were not more likely to be in longer-gapped, four-generation lineages. DISCUSSION The majority of the adult population in the early 1990s was in three-generation lineages. The verdict is still out on whether population aging results in the wholesale verticalization of lineages. Social differentials in four-generation lineages in the early 1990s were mainly due to differences in the timing of fertility, rather than mortality.