It depends on what constitutes "sexual assault". Some women even consider being hit on by guys they find unattractive as sexual assault, which might explain the high percentage.
If you had spent more than a second writing this reply or more likely if you weren't an iredeemable rape apologist, you wouldn't perpetuate victim-blaming myths. The study itself says: http://www.plosone.org/article/info:doi/10.1371/journal.pone.0102172The survey used operationalized definitions of phenomena generally characterized as “harassment” by the United States Equal Employment Opportunity Commission [17], and “assault” by WomensLaw.org [20] without specifically using the terms “harassment” or “assault” to avoid making respondents name their experiences (see Materials S1 for the full survey).