The Census Bureau announced today that the first numbers from the 2010 Census will be released on Tuesday, Dec. 21. These include resident population totals for each state (and D.C. and the nation), as well as apportionment population totals that are used to divide the 435 seats in the U.S. House of Representatives among the states. The apportionment totals include the resident population for each state, as well the number of overseas members of the military and federal workforce (plus dependents living with them) who can be allocated back to a particular state.

The bureau also has a nifty interactive map showing population change and apportionment trends going back to 1910. Click on the reapportionment map for 1920, and there is no data shown. That’s because Congress refused to reapportion that year because officials from rural areas feared the loss of power to growing cities.

This year’s release is a week earlier than in 2000, when the reapportionment and resident population totals were released on Dec. 28, 2000.  A dozen seats in the U.S. House changed hands in 2000, with Southern and Western states gaining at the expense of those in the Northeast and Midwest. The same general pattern is expected from the 2010 Census, reflecting a long-term pattern of national population change.