"By 2030, more than 20 percent of U.S. residents are projected to be aged 65 and over, compared with 13 percent in 2010 and 9.8 percent in 1970," according to a 2014 report from the Census Bureau.
Colby, S. L., & Ortman, J. M. (2104). The baby boom cohort in the United States: 2012 to 2060. (Current Population Reports No. P25-1141). Washington, DC: U. S. Census Bureau. Retrieved from www.census.gov.