The sources of data for the need variables shall be data that are available and collected in a uniform manner that can be confirmed and verified for all AIAN households and persons living in an identified area. Until fiscal year 2018, the data used are 2000 U.S. Decennial Census data and any HUD-accepted Census challenges. The 2000 U.S. Decennial Census data shall be adjusted annually using IHS projections based upon birth and death rate data provided by the National Center for Health Statistics.

Beginning fiscal year 2018, the data source used to determine the AIAN persons variable described in § 1000.324(g) shall be the most recent U.S. Decennial Census data adjusted for any statistically significant undercount for AIAN population confirmed by the U.S. Census Bureau and updated annually using the U.S. Census Bureau county level Population Estimates for Native Americans. For Remote Alaska as designated by the U.S. Census Bureau, Alaska Formula Areas in Remote Alaska shall be treated as Reservation and Trust Lands, unless the U.S. Census Bureau includes Remote Alaska in their Census Coverage Measurement or comparable study. The data under this paragraph (b) shall be updated annually using the U.S. Census Bureau county level Population Estimates for Native Americans.

Beginning fiscal year 2018, the data source used to determine the variables described in paragraphs (a) through (f) of § 1000.324 shall initially be the American Community Survey (ACS) 5-year Estimates.

Indian tribes may challenge the data described in this section pursuant to § 1000.336.