Is the incidence of sexual child abuse on the rise, or is it just that a greater percentage are being reported?

A young girl I know of recently came out and shared with her family the fact that she had been sexually molested in the past. She also shared it with a close (girl) friend, and it turns out that the friend had had a similar experience in the past. The victim’s mom, and also the friend’s mom were each victims of sexual abuse as children.

I don’t recall hearing about such experiences in the past, say 30–40 years ago, and I wonder if the pattern of behavior is on the rise, or are children just being encouraged to report it.