Historical events greatly influence the number of children born in a society, and two events during recent American history—the Great Depression and World War II—have shaped present-day demographics in the United States. During the early years of the Great Depression (1929–39), fewer babies were born because most people could not support large families. The small number of births during this time resulted in a relatively small population who were in their late forties and early fifties during the 1980s.
In contrast, the birth rate boomed during the years following World War II (1939–45). After ten years of economic hardship and four years of war, many Americans who had delayed starting a family wanted to have children during the post-war economic boom. During the period from 1946 to 1964 the United States recorded its highest-ever number of births. Figure 1.1, Figure 1.2, and Figure 1.3 are population pyramids, graphical representations of the age and gender distribution of a population. In the pyramids the letters BB represent the age groups that are part of the baby boom generation. The bulge representing baby boomers moves higher on the pyramid as decades pass and baby boomers age. Boomers were in their midtwenties to mid-forties during the 1990s, their mid-thirties to mid-fifties in 2000, and will be in their sixties and seventies by the year 2025.
According to the Federal Interagency Forum on Child and Family Statistics (America's Children in Brief: Key National Indicators of Well-Being, 2004, Washington, DC, 2004, http://childstats.gov/ac2004/tables [accessed August 24, 2004]), in 2002 72.9 million children younger than the age of eighteen lived in the United States. This number is expected to increase to 80.3 million in 2020. However, because the country's entire population will increase, the percentage of children in the population will actually remain fairly steady, decreasing slightly from 25% in 2002 to 24% by 2020.
Family and Household Size
The composition of households in American society changed markedly in the twentieth century. According to the 2002 Census Bureau Report on demographic trends in the twentieth century, in 1950 families accounted for 89.4% of all households. By 2000 that number had decreased to
68.1%. The proportion of married-couple households that included at least one child under the age of eighteen has also decreased. In 1960 59.3% of married-couple households included at least one child under the age of eighteen, but by 2000 only 45.3% of these households had a child under eighteen living at home. (See Figure 1.4.)
The American family shrank in size during the twentieth century. In 1900 most households consisted of five or more people. By 1950 two-person families became the most common family type and remained so to the end of the century. The proportion of one- and two-person households increased from 1950 to 2000, while the proportion of households with three or more people steadily decreased. (See Figure 1.5.) Average household size declined from 4.6 people per household at the beginning of the century to 2.6 people in 2000. This was true partly because the population was getting older.