"Overall, 16.7 percent of workers provided eldercare. Part-time workers did so at a higher rate (18.1 percent) than did full-time workers (16.3 percent)," according to a 2013 analysis of data from the American Time Use Survey.
Bureau of Labor Statistics. (2013). Eldercare in 2011 and 2012. TED: The editor's desk. Retrieved September 20, 2013, from www.bls.gov.