Hayford and Furstenberg, January 2005, page 1 of 17
Is 30 the New 20? Trends in Age Distribution of Problem Behaviors in Young Adulthood
Since the early twentieth century, when the concept of adolescence as a separate life
stage was first proposed, the process of becoming an adult has changed substantially. The
transition to adulthood was compressed and standardized during the first half of the century, then
stretched out and individualized during the later part of the century. In this paper, we examine
the consequences of changes in the acquisition of adult roles for the nature of adolescence and
young adulthood, as reflected in the age distribution of "problem" behaviors historically
associated with adolescence.
The term adolescence was introduced to describe the distinct period between childhood
and adulthood. It encompasses physical development and puberty, but it is also a period of
cognitive and psychological development. The end of adolescence, and the entry into adulthood,
is signaled by a series of transitions, such as finishing school, entering the work force, leaving
the parental home, marrying, and becoming a parent (Hogan and Astone 1986). Taken alone,
none of these transitions is either necessary or sufficient for the achievement of adult status, but
taken together, they mark the adult stage of life course development.
During the first half of the twentieth century, the transition to adulthood became
increasingly institutionalized (Modell 1989). Within individual life courses, the timing of role
changes was compressed, as school-leaving, employment, marriage, and parenthood all took
place within a period of a few years for most young people. At the same time, variation across
individuals in the timing of key events, such as marriage and parenthood, decreased. This
compression and standardization reached its peak during the Baby Boom years.
Since the Baby Boom, virtually all of these markers of adulthood have been shifted to
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Convention