Proponents of cultural diversity may be unhappy to learn that many of the nearly 40 million U.S. immigrants are already on the road to assimilation. To determine how similar various immigrant groups are to native-born Americans, the Manhattan Institute for Policy Research, a libertarian think tank, measured three kinds of factors: economic, cultural, and civic. According to a report on the study in the May 13 edition of USA Today, Canadians ranked highest at 53%. Filipinos scored 49%, Cubans 43%, Koreans and Vietnamese 41%, Chinese 21%, Salvadorans 18%, and Indians 16%. Interestingly, the largest immigrant group–Mexicans–is among the most self-contained, with an assimilation rating of only 13%.