In Summary File 3, population tables are identified with a "P" and housing tables are identified with an "H" prefix, followed by a sequential number. The "P" and "H" tables are shown for the block group and higher levels of geography, while the "PCT" and "HCT" tables are shown for the census tract and higher levels of geography. There are 16 "P" tables, 15 "PCT" tables, and 20 "HCT" tables that bear an alphabetic suffix on the table number, indicating that they are repeated for nine major race and Hispanic or Latino groups. Summary File 3 contains a total of 813 unique tables -- 484 population tables and 329 housing tables compiled from a sample of approximately 19 million housing units (about 1 in 6 households) that received the Census 2000 long-form questionnaire. Fifty-one tables are repeated for nine major race and Hispanic or Latino groups: White alone; Black or African American alone; American Indian and Alaska Native alone; Asian alone; Native Hawaiian and Other Pacific Islander alone; Some other race alone; Two or more races; Hispanic or Latino; and White alone, not Hispanic or Latino.

Summary File 3 presents data in a hierarchical sequence down to the block group for many tabulations, but only to the census tract levels for others. Summaries are included for other geographic areas such as Zip Code Tabulation Areas (ZCTAs^™) and Congressional districts (106^th and 108^th Congress).