	A 2002 study found an average of 18.6% European genetic contribution and 2.7% Native American genetic contribution (with standard errors 1.5% and 1.4% respectively) in a sample of 232 African Americans. Meanwhile, in a sample of 187 European Americans from State College, Pennsylvania, there was an average of 0.7% West African genetic contribution and 3.2% Native American genetic contribution (with standard errors 0.9% and 1.6% respectively). Most of the non-European admixture was concentrated in 30% of the sample, with West African admixture ranging from 2 to 20%, with an average of 2.3%.