Moreover, a similar study published in 2009 by Stephanie K. McWhorter, which examined 1,149 navy recruits who'd never been convicted of sexual assault, replicated Lisak's findings: 144 of the recruits (13 percent) turned out to be undetected rapists, and 71 percent of these 144 rapists were repeat offenders. An average of 6.3 rapes or attempted rapes could be attributed to each of them. Of the 865 rapes and attempted rapes reported in McWhorter's study, 95 percent of the assaults were committed by just 96 individuals. As Lisak had reported, a small number of indiscernible offenders--only 8.4 percent of the population studied--were responsible for a staggering number of rapes. It should be noted that all of the subjects in the studies by Lisak and McWhorter participated voluntarily and that none of the undetected rapists identified by the researchers considered themselves rapists.