The Commerce Department's Census Bureau released data today showing 3.9 million multigenerational family households in 2000, nearly 4 percent of all households. It is the first time the Census Bureau has analyzed multigenerational family households those consisting of three or more generations of parents and their children.

     The data are contained in a Census 2000 Brief, Households and Families [pdf], (Detailed Table), which looks at how the composition of the country's households has changed since the 1990 census.

     Of the multigenerational family households identified in the brief, about two-thirds (2.6 million) consisted of the householder and the householder's children and grandchildren. Another one-third (1.3 million) consisted of the householder and the householder's children and parents (or parents-in-law). Another 78,000 households, about 2 percent of all multigenerational family households, consisted of four generations.

     "Multigenerational families are more likely to reside in areas of recent immigration, where new immigrants may live with their relatives," said demographer Tavia Simmons, who co-authored the study. "They also are more common in areas where housing shortages or high costs may force families to double up their living arrangements or in areas with relatively high rates of out-of-wedlock childbearing, where unwed mothers live with their children in their parents' home."

     Hawaii (8.2 percent), California (5.6 percent), and Mississippi (5.2 percent) had the three highest proportions of multigenerational households in the nation. North Dakota had the lowest, with 1.1 percent.

     According to the brief, the most common type of household in the country, those consisting of married-couple families (54.5 million), declined from 55.2 percent of all households in 1990 to 51.7 percent in 2000. And the second most common type, those consisting of people living alone, rose slightly from 24.6 percent to 25.8 percent of all households for a total of 27.2 million.

     Living arrangements differ greatly from one part of the country to another. "Counties with the highest proportion of married-couple households were located in Utah and Idaho and in the West Central section of the country, from west Texas northwards," said Grace O'Neill, the brief's other author. "On the other hand, the counties in the coastal states extending from the lower Mississippi Valley up the Atlantic seaboard to New England had the lowest proportions."

     The percentage of people living alone, a characteristic of people in different stages of life from young adults to the elderly, was similarly high in places as diverse as Seattle, Wash., Fort Lauderdale, Fla., and St. Louis, Mo., which each had 40 percent or more of their households consisting of people living alone.

     Unmarried partner households, which may or may not contain children or other relatives of the householder, numbered 5.5 million in 2000; 4.9 million of them consisted of partners of the opposite sex.

     Also today, the Census Bureau released the Grandparent's Day Facts for Features, a brief compendium of current Census Bureau statistics pertaining to grandparents.

     Additional Census 2000 briefs will be released over the next few months on topics such as age, sex and housing characteristics. A listing of Census 2000 briefs can be found on the Census Bureau's Web site at http://www.census.gov/population/www/cen2000/briefs.html.