In 2015, 64.7 million U.S. residents spoke a language other than English at home, according to data from the Census Bureau. Mainly as a consequence of mass immigration, this is double the number in 1990 when 31.8 million spoke another language at home. Furthermore, the 2015 total is almost triple the total of 1980. In terms of percentage, 11 percent of residents in 1980 spoke a non-English language at home, compared with the 2015 percentage of 21.5 percent.
Read more at cis.org.