<P> Between 1960 and 1990 the census questionnaire in Puerto Rico did not ask about race or ethnicity . The 2000 United States Census included a racial self - identification question in Puerto Rico . According to the census, most Puerto Ricans identified as White and Hispanic; few identified as Black or some other race . </P> <P> A recent population genetics study conducted in Puerto Rico suggests that between 52.6% and 84% of the population possess some degree of Amerindian mitochondrial DNA (mtDNA) in their maternal ancestry, usually in a combination with other ancestries such as aboriginal Guanche North - West African ancestry brought by Spanish settlers from the Canary Islands . In addition, these DNA studies show Amerindian ancestry in addition to the Taíno . </P> <P> One genetic study on the racial makeup of Puerto Ricans (including all races) found them to be roughly around 61% West Eurasian / North African (overwhelmingly of Spanish provenance), 27% Sub-Saharan African and 11% Native American . Another genetic study from 2007, claimed that "the average genomewide individual (ie . Puerto Rican) ancestry proportions have been estimated as 66%, 18%, and 16%, for European, West African, and Native American, respectively ." Other study estimates 63.7% European, 21.2% (Sub-Saharan) African, and 15.2% Native American; European ancestry is more prevalent in the West and in Central Puerto Rico, African in Eastern Puerto Rico, and Native American in Northern Puerto Rico . </P> <P> A Pew Research survey indicated a literacy rate of 90.4% (adult population) in 2012 based on data from the United Nations and a life expectancy of 79.3 years . </P>

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