All Things Census
The Census Bureau is releasing demographic profiles from the 2010 Census this month, and here is a look at the first round of news stories from the data, which focused on young people, older Americans, the national origin of Hispanics and changes in household size:
When census-takers can’t reach anyone at a particular address or obtain information about occupants in other ways, they sometimes use a last-resort statistical technique called “imputation” to fill in missing data. One marker of the quality of a census is how much it relies on imputation to add people to the count.
In the most extreme cases, census-takers have only an address taken from a master list drawn up in cooperation with local officials. They may not even know that a housing unit exists at that address, much less who lives there. If the address is indeed found to be an apparent dwelling place, the census-taker may not be able to get anyone to come to the door, and neither neighbors nor building managers may be willing and able to supply information. Yet the Census Bureau’s orders are to count everyone living in the U.S. on April 1, Census Day.
So to meet the goal of having a complete and accurate census, the Census Bureau imputes the existence and number of people living at the address in question, a procedure known as “count imputation.” (The other kind of imputation, called “characteristic imputation,” is when the Census Bureau has a head count for an address but is missing race, age or other personal information.) The number of imputed people tends to be higher among hard-to-count groups such as ethnic and racial minorities.
In 2010, according to figures supplied by the Census Bureau, 1,163,462 people were added to the household population (the total excluding group quarters) via count imputation, or .39% (less than one half of one percent) of the total. This served to boost the household population to slightly more than 300 million; pre-imputation, it stood at 299,594,753.
By comparison, in the 2000 Census, 1,172,144 people were added to the household population via count imputation, or .43% of the total. Read more
Canadians began receiving yellow envelopes this week with their census forms, which include a secure access code so they can complete the questionnaire online. Canadians are being asked to complete the census short form, which is mandatory, within 10 days. If the form is not received by June, a census-taker will knock on the door to get the information. The Statistics Canada website provides detailed information about how to count part-time residents, such as college students or children in joint custody.
The Canadian census does not include a mandatory long form this year, but instead will send a voluntary household survey in about a month. Government officials say they dropped the long form because of privacy concerns expressed by Canadians. The decision was criticized by genealogists and others; the government’s chief statistician resigned because he disagreed with it.
Latinos represent 16.3% of the U.S. population, but were only 7% of the voters in last November’s elections, according to a report based on census data that was released today by the Pew Hispanic Center, a project of the Pew Research Center. This disparity in population and electorate proportions is driven by essentially two factors in the Hispanic population: Youth and non-citizenship.
To be sure, more than 6.6 million Latinos voted last November, a record for a midterm election. And the Latino share of the electorate has risen; it was 6% in 2006. But because so many Hispanics are under age 18 (35%) and so many adult Hispanics are not citizens (22%), “the share of the Latino population that is eligible to vote is smaller than it is among any other group,” according to the report. In addition, Latino turnout was lower than that of white or black voters; one reason is that a large share of Hispanic voters are under 30, and this group tends to participate in elections less than older voters do. The report also analyzes turnout by Latino sub-group, examines numbers in states that allow early voting and compares reasons why people say they did not vote.
The data for this report–“The Latino Electorate in 2010: More Voters, More Non-Voters”–are derived from the November Voting and Registration Supplement of the Current Population Survey (CPS). The CPS is a monthly survey of about 55,000 households conducted by the Census Bureau for the Bureau of Labor Statistics. Author of the report is Mark Hugo Lopez, associate director of the Pew Hispanic Center.
Census 2010 datasets are finding a second home on the websites of think tanks, state data centers and advocacy groups that have repackaged the numbers in easy-to-use look-up formats. These sites are especially useful for people who only want one or two numbers, or who have not yet mastered the details of the American FactFinder look-up tool on the Census Bureau website.
For example, the Census Bureau last week released population counts, down to the block level, for seven kinds of group quarters, but the numbers are only available via the bureau’s data-firehose FTP site, which is intended for expert users. (An All Things Census posting in February explains why these numbers are being released earlier than usual.) Two public policy advocacy groups, the Prison Policy Institute and Demos, have released a free look-up tool with block-level tables of correctional facilities, searchable by county.
Using the bureau’s redistricting file, the US2010 project has posted easy look-ups of race and ethnic data for metropolitan areas and for cities with populations of 10,000 or more, as well as residential segregation indices. CensusScope has a rich trove of counts from the 2010 Census and earlier censuses for total populations, race/ethnic groups and the race/ethnic composition of the child populations for states, metropolitan areas, counties and cities (and metro-area segregation indices). And, of course, the Pew Hispanic Center has 2000 and 2010 Hispanic and non-Hispanic census counts for every state and county.
Many State Data Centers (here is a map with links to all of them) have repackaged census data for their localities in simple-to-use tables. In Alaska, the look-up includes Alaska native villages and tribal areas as well as cities, boroughs and other units of geography. California offers detailed data and some numbers from earlier years. Colorado offers rankings as well as data. Connecticut offers a color-coded map of population change and Indiana has population maps by school district and other geographies. Pennsylvania has detailed group quarters numbers for each of its counties.
The average size of U.S. households has been declining for decades, but may have grown in recent years, at least in part because of an increase in multi-generational households. Data from the 2010 Census will supply additional information about whether, where and why this is happening.
Meanwhile, here is an early clue: Average household size in Maryland, which had declined in the 1970s, 1980s and 1990s, grew by a tiny amount from 2000 to 2010, according to numbers analyzed by the Maryland State Data Center. In 1970, average household size was 3.25 in Maryland; in 1980, it was 2.82; in 1990, 2.67; in 2000, 2.61. In 2010, it was again 2.61 (the 2000 and 2010 numbers look the same, but the data center analysis shows there actually was an increase of .01 before rounding). Household size grew in several large suburban counties, according to the analysis.
The Census Bureau plans to release statistics on household size in May, but they can be calculated now based on other data released by the bureau this week. To accommodate states such as Maryland that want to take account of prison populations in legislative redistricting, the bureau released detailed counts of populations for group quarters (including prisons). If group quarters counts are subtracted from the total population counts released earlier, the number of people living in households can be derived, then divided by the number of occupied housing units included in the bureau’s recently released redistricting files to produce average household size.
In addition to publishing detailed numbers from the 2010 Census, the Census Bureau has been releasing performance indicators from the count. They offer clues to help answer the question of how well the bureau did in counting the entire U.S. population, only once, and in the right place.
The most crucial evidence, an independent post-census quality survey, will not be published until next year. That survey will produce measurements of undercounts and overcounts of specific race and Hispanic groups. However, other information is available now that speaks to the completeness of the count as well as to its data quality. This posting explains some of these key metrics and places them in a chronological narrative of the census-taking process.
Mail Participation Rate: The Census Bureau mailed millions of forms in March 2010. An early important indicator was the mail participation rate: 72% of occupied households sent back their forms, the same as for the short form in 2000. This was a good result, both for cost and quality. Non-response follow-up is expensive, and mailed-in census forms tend to have more accurate information than can be obtained from interviews weeks or months after Census Day, April 1. Read more
More than 2,000 demographers, sociologists and others converged on Washington, D.C., last week for the Population Association of America’s annual meeting. Among the poster sessions and papers presented were some that dispute the popular (or academic) wisdom about important aspects of family life. Three are described here, along with Pew Research Center survey findings that bear on the topics they cover—family meals, cohabitation and divorce.
Conference presentations are typically works-in-progress, to be revised as more information becomes available or challenges to their methodology are resolved. They are not the final word on these topics, and should not be taken as the new conventional wisdom. But they raise valuable questions about substantive issues. Read more
Now that the 2010 Census numbers have been released for every place in the United States, a number of local officials—including the mayors of New York and Detroit—have announced plans to file administrative challenges to counts that they contend are too low. Based on past patterns, some lawsuits alleging undercounts also can be expected.
Census numbers indicated that New York City’s population in 2010 was 8,175,133, compared with 8,008,278 a decade earlier. That gain of about 167,000 people was smaller than expected, and city officials say it was less than the number of new housing units added over the decade. Mayor Michael Bloomberg announced the city will file a formal challenge, focusing on problems in Brooklyn and Queens.
The mayor of Detroit, Dave Bing, hopes a challenge could increase his city’s official count of 713,777 to about 750,000. As counted by the Census Bureau, Detroit’s population fell by 25% from 2000 to 2010. Both city and regional officials say the official count could be low by tens of thousands of people.
Both cities will appeal under the Census Bureau’s Count Question Resolution program, which offers a limited opportunity to challenge the numbers. Any changes would not affect apportionment of congressional seats, counts for redistricting purposes or official census data products. The changes would be incorporated into Census Bureau population estimates, which federal agencies use as the basis for dividing program funds among the nation’s states and localities for the next decade. Read more
When final national race counts from the 2010 Census were released last month, they included more than 9 million Americans who self-identified as belonging to two or more race groups. One of them was not President Barack Obama, child of a white mother and black father, who said last year that he described himself on his census form as “black.”
As columnist Gregory Rodriguez recently pointed out, the number of Americans who checked both “black” and “white” on their census forms grew by 134% from 2000 to 2010. (Among non-Hispanics, about 1.6 million reported being both black and white, but not any other race; among Hispanics, about 654,000 did so.) Rodriguez lamented the president’s decision not to include himself in more than one racial category.
The perception of Obama’s racial identity is quite different among black and white Americans, according to a Pew Research Center survey on race in late 2009 that asked respondents “do you think of Obama as black or mixed race?” Among non-Hispanic whites, 53% said the president was mixed race, but 55% of non-Hispanic blacks said he was black. Among Hispanics of all races, 61% said Obama is mixed race.