Per capita income is the mean income computed for every man, woman, and child in a particular group including those living in group quarters. It is derived by dividing the aggregate income of a particular group by the total population in that group. (The aggregate used to calculate per capita income is rounded. For more information, see "Aggregate" under "Derived Measures.") Per capita income is rounded to the nearest whole dollar. (For more information on means, see "Derived Measures.")

Income components were reported for the 12 months preceding the interview month. Monthly Consumer Price Indices (CPI) factors were used to inflation-adjust these components to a reference calendar year (January through December). For example, a household interviewed in March 2007 reports their income for March 2007 through February 2007. Their income is adjusted to the 2007 reference calendar year by multiplying their reported income by 2007 average annual CPI (January-December 2007) and then dividing by the average CPI for March 2006-February2007.
In order to inflate income amounts from previous years, the dollar values on individual records are inflated to the latest years dollar values by multiplying by a factor equal to the average annual CPI-U-RS factor for the current year, divided by the average annual CPI-U-RS factor for the earlier/earliest year.

A person having origins in any of the original peoples of North and South America (including Central America) and who maintain tribal affiliation or community attachment. It includes people who classified themselves as described below.
American Indian -This category includes people who indicate their race as "American Indian," entered the name of an Indian tribe, or reported such entries as Canadian Indian, French American Indian, or Spanish American Indian.
American Indian Tribe -Respondents who identified themselves as American Indian were asked to report their enrolled or principal tribe. Therefore, tribal data in tabulations reflect the written entries reported on the questionnaires. Some of the entries (for example, Iroquois, Sioux, Colorado River, and Flathead) represent nations or reservations. The information on tribe is based on self-identification and therefore does not reflect any designation of a federally- or state-recognized tribe. The information for the American Community Survey is derived from the American Indian Tribal Classification List for the 1990 census that was updated for Census 2000 and the ACS based on a December 1997Federal Register Notice entitled "Indian Entities Recognized and Eligible to Receive Service From the United States Bureau of Indian Affairs," Department of the Interior, Bureau of Indian Affairs, issued by the Office of Management and Budget.
Alaska Native - This category includes written responses of Eskimos, Aleuts, and Alaska Indians as well as entries such as Arctic Slope, Inupiat, Yupik, Alutiiq, Egegik, and Pribilovian. The Alaska tribes are the Alaskan Athabascan, Tlingit, and Haida. The information for ACS is based on the American Indian Tribal Classification List for the 1990 census and Census 2000, which was expanded to list the individual Alaska Native Villages when provided as a written response for race.