The Short Answer: April 2011 through September 2013
Summary files for the 2010 Census data will be released “on a flow basis from April 2011 through September 2013.”
The Long Answer:
Population counts will be delivered to President Obama within nine months of Census Day (on or before Dec. 31, 2010), as required by law. This data will include “the apportionment population counts by state, and the number of seats in the U.S. House of Representatives apportioned to each state.”
Also, “Public Law (P.L.) 94-171 requires the Census Bureau to provide only counts of the total population for a variety of geographic areas to be used for the redistricting process. In addition, other data items, such as race, ethnicity, voting age and housing unit tallies, are included in this data set. P.L.94-171 also requires these data be delivered to each state no later than April 1, 2011.”
You can find this information in the 2010 Census Constituent FAQs.
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