Population of the United States by Race and Hispanic/Latino Origin, Census 2000 and 2010
|Race and Hispanic/Latino origin||Census 2010,|
|Black or African American||37,685,848||12.2||34,658,190||12.3|
|American Indian and Alaska Native||2,247,098||.7||2,475,956||0.9|
|Native Hawaiian and other Pacific Islander||481,576||0.15||398,835||0.1|
|Two or more races||5,966,481||1.9||6,826,228||2.4|
|Some other race||604,265|
|Hispanic or Latino||50,477,594||16.3||35,305,818||12.5|
NOTE: Percentages do not add up to 100% due to rounding and because Hispanics may be of any race and are therefore counted under more than one category.
The Census Categories
Due to the certainty with which racial categories are used, it's easy to assume they're based on some firm grounding principle. However, as with all censuses, the categories used in the U.S. Census are chosen and revised each cycle to reflect the divisions that are considered relevant. That is to say, the reason that the Census Bureau tracks "American Indian and Alaska Native" and doesn't track categories like "Arab" isn't because there's some scientific reason that "Indian" is a race and "Arab is not. It's because at the time of the 2010 census it was decided that the status of American Indian was important to keep track of for demographic purpose, and that Arab was not.
For a comparison, consider these categories from the comparable U.K. 2011 Census.
How the Category of "Hispanic" Has Evolved
The Hispanic category in the census has changed throughout the decades. Except for a one-time "Mexican" racial category in 1930, the first attempt to track the population that was "Mexican, Puerto Rican, Cuban, Central or South American," or "Other Spanish" was in 1970. In that year and in the next three censuses, the census bureau kept receiving a great deal of erroneous responses, so they redesigned the question for greater clarity. In 1970, some people from the Midwest or the South mistakenly identified as "Central or South American," and many more did not identify themselves with the target nationalities despite being of Latin American descent. The most recent census, which introduced the wording of "Latino," saw a significant upturn in responses from U.S.-born Latino persons.
Source: U.S. Census Bureau: National Population Estimates; Decennial Census.