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    FederalUS Census MethodologyU.S. Department of Health & Human Services — US Census Annual Estimates of the Resident Population for Selected Age Groups by Sex for the United States. The estimates are based on the 2010 Census and reflect...
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    FederalBehavior Risk Factor Surveillance System (BRFSS) Glossary and MethodologyU.S. Department of Health & Human Services — Download the latest version of the Glossary and Methodology File
