In a study published on June 19, 2013, the Pew Research Hispanic Center chronicles the 14 largest origins groups of American Hispanics, a population group of approximately 51.2 million in 2011. Among American Hispanics, nearly 65% are of Mexican origin. The next largest Hispanic origin group is Puerto Rican at around 9%.
Source: Pew Research Hispanic Center
The report is linked below:
Pew Hispanic Center: Hispanic Origins Groups