Perhaps not compared to, say, car accidents in the U.S., but that doesn't by any means imply that it's rare enough to not be a valid concern for potential victims.

From the wikipedia article cited above:

"Rape prevalence among women in the U.S. (the percentage of women who experienced rape at least once in their lifetime so far) is in the range of 15%-20%, with different studies agreeing with each other.

I'm personally not aware of any statistics that would justify calling rape an 'ultra-rare' occurrence in any part of the world; perhaps someone will enlighten me.