Just read a fascinating article which claims that around 75% of adults will experience SP at some point in their lives - I had no idea the numbers were so large!
I had a few nasty bouts when I was in my late teens and early 20s (along with chronic insomnia, depression and anxiety - yeah, that was a fun time!), but they tailed off as I grew older and I don't think I've had an episode for about two or three years.
What are your experiences?