Families, Demographic Trends

This entry reviews various demographic trends and, in so doing, illustrates the fluidity and complexity of families. Before beginning the discussion, it is [Page 604]worthwhile to review a few terms. Demography is a study of characteristics pertaining to the human population, such as fertility, mortality, structure and distribution, geographic mobility, immigration, emigration, and population density. This includes examining changes over time. Family demography involves examining factors associated specifically with the family, such as number of families, presence of children, living arrangements, and relationship status. Much of this information can be obtained from U.S. Census data, which contains a collection of demographic information. This enumeration (or headcount) is mandated by the U.S. Constitution. In a U.S. Census Current Population Report developed by Jason Fields (2004), family living arrangements were reviewed.

According to Fields's (2004) report, the Census Bureau developed two typologies—family households and family groups—in an attempt to assess demographic characteristics of families.

• Family households: A household is defined as everyone residing in a housing unit. It may consist of one or more people. The householder is the person who rents or owns the unit. There are family households and nonfamily households. Unlike a household, a family household consists of at least two related people; these people can be related by marriage, birth, or adoption. One of these people is the householder. Children may or may not be present in family households. Family households, according to definitions provided by the census, are maintained either by married couples or by a man or a woman with whom other kin are living. Identifying family households entails asking who in the home is related to the householder.
• Family groups: Identifying family groups entails counting family units. In this case, the householder may or may not be a member of the family. This means that family groups include all related and unrelated subfamilies. An example of an unrelated subfamily is a married couple who is not related to the householder. An example of a related subfamily is an offspring and that offspring's spouse living in the household of the offspring's parents.

There were about 76 million family households and 79 million family groups in the United States in 2003.

A factor that generally comes to mind when discussing families is the presence of children. About 60 percent of nonmarried-couple family groups and 45 percent of married-couple family groups included an own child under the age of 18 years in 2003. The proportion of large family groups with children decreased between 1970 and 2003. For example, the proportion of family groups with four or more children was 17 percent in 1970, 8 percent in 1980, 5 percent in 1990, and 5 percent in 2003. Some children living in the homes were older. In 1960, 52 percent of family households included a male adult child aged 18 to 24. In 2006, that figure was 53.7 percent. In 2006, about 14.3 percent of family households included male children aged 25 to 34 living with their parents and 9 percent included adult female children in that age range. There are many possible reasons that adult children return to their parents' home; they may return in need of support as a result of job loss, poor economy, or divorce.

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