Population Research and Policy Review 16: 415–434, 1997.
1997 Kluwer Academic Publishers. Printed in the Netherlands.
Trends in American family size diversity
RALPH R. SELL & STEPHEN J. KUNITZ
Center for Governmental Research Inc., Rochester, NY; University of Rochester, Rochester,
Abstract. How diverse is American society and are Americans becoming more or less diverse?
Contemporary discussions claim high and increasing diversity, but analyze few actual trends.
This paper examines completed family size diversity from 1940 to 2000 by race and across
US states. For all groups, regions and the USA as a whole, family size diversity decreased
signiﬁcantly, produced by a combination of fewer small and large families and a general
decline in regionally-based differences. Both within and across states the diversity declined
in two stages, but regional clusters of states followed different paths. A cluster of Southern
Mountain states showed the greatest contrast. Between the 1940s and the early 1970s, a slight
baby boom rise in diversity among homogeneous states, was counterbalanced by declining
diversity in more diverse states. Black women in all states and white women in Mainstream
and Other states showed similar trends during the baby boom years, while white women in
the Southern Mountain states failed to show a baby boom increase in large families. For
childbearing completed since 1975, regional patterns disappeared and both the range and level
of diversity declined further. A national and essentially homogeneous culture of childbearing,
initiated during the baby boom years and now facilitated by birth control and abortion, has
settled in at below-replacement levels. While the possibility always exists that childbearing
pattern might change, there is no current evidence to suggest movement away from this low
and homogeneous fertility.
Key words: Baby boom, Cultural diversity, Fertility trends
More or less diversity?
How diverse is American society and are Americans living in different states
becoming more like or different from each other? In what ways can demo-
graphic data and techniques contribute answers to these questions? Except
for race/ethnicity, the actual evidence about either trends or a high level of
American diversity is much less.
In fact before the contemporary focus on
diversity, many ‘mass society’ scholars thought that marketing and other cap-
italist forces had produced a national homogenization that enabled products
to be produced and marketed with little attention to regional variation in tastes
and preferences (Kornhauser 1959). This homogenization and resulting social