41 recorded, on the Pacific Coast, since 1950 according to a Shark Research Committe report I read awhile back.
There were 100+, if IIRC, attacks reported during that period if you include swimmers, divers, etc., etc.
Pretty rare considering how many people take to the water every year. That's why I personally never worried about it.
I was more concerned about getting hit by an out of control board...and that happened several times.