On March 14, the Final Criteria and Program Implementation statements for census tracts and block groups, for the 2010 decennial census, were published in the Federal Register.
Most of the changes proposed in the proposed criteria (published April 7, 2007) were adopted. These include the use of housing unit counts rather than population counts as criteria for tract delineation, permitting delineation of census tracts for special land uses (e.g., airports, large parks), and a change in the approach to tracts within federally recognized American Indian reservations and off-reservation trust lands. The proposal to delineate separate tracts for large water bodies was rejected.
The principle of tract comparability over time is reiterated in the new regulation, including the strong suggestion that changes should involve either splitting tracts (when they have grown too large) or
combining them when they have become too small.