| Census 2000
The US Census Bureau counts the nation's population and housing units every 10 years. The data are used in the 50 states to determine how seats in the US House of Representatives are apportioned; they are also used to draw congressional and state legislative district boundaries and to allocate federal and state funds. Although the District does not have congressional representation, these data are used by the Council of the District of Columbia to officially restructure ward and ANC boundaries for the next decade. Certain Census 2000 results are now available for the District of Columbia.
Two changes distinguish Census 2000 race categories from those in previous censuses. First, the "Asian or Pacific Islander" category has been divided into two categories, "Asian" and "Native Hawaiian and Other Pacific Islander." Tables of population by race for the year 2000 show counts for each of these two new race categories. However, in tables of population change from 1990 to 2000, the two categories for the year 2000 are re-combined to allow for comparison with 1990.
In a more sweeping change, Census 2000 was the first to allow respondents to identify themselves by more than one race. A person could choose a single race, for example, "Black," or a combination, "Black, White, and Asian." Tables using the expression "single race" count persons in a race category only if they have designated that race alone. This gives the minimal count for each race. In these tables, all combinations of races are placed in a separate category entitled "two or more races".
As in past censuses "Hispanic/Latino" is not a race category. Persons of Hispanic origin may be of any race. Therefore each race category contains persons of both Hispanic and non-Hispanic origin.
The census divides households into two broad categories, family and non-family. Each category contains many subcategories; the tables listed below contain information on the most frequently requested household subcategories. | 
