Thinking it might be the (poor) quality of the data, we obtained a large sample of similar data from a different source: supplier contracts.

FORBES: Most People Don't Know Their Business (so asking them about it is useless)

The Army Corps, the U.S. Fish and Wildlife Service and the U.S. Geological Survey continue to study the issue and hope within a couple of years to refine methods of determining the likely source of a particular DNA sample, she said.

WSJ: Report: Asian carp may have reached Great Lakes

The analysis, based on a sample survey of voters last year, is viewed as the best source of government data on turnout by race and ethnicity.

NPR: A Census First: Black Voter Turnout Passes Whites