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on or before December 31, 2010 -- "the apportionment population counts, by state, and the number of seats in the US House of Representatives apportioned to each state"
on or before April 1, 2011 -- "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."
on a flow basis from April 2011 through September 2013 -- "Other data products such as demographic profiles, summary files of aggregated data, and reports"