So the answers to those questions are gonna be pretty bleak, just to warn you before I try to answer them with what I’ve found.
To start, google is too crippled for me to find your first question. But if you pick a city and search the numbers are pretty horrifying.
Yes, they move the priests around. It’s known as priest shuffling. via wikipedia
Much like you, I was curious as to how long this has been going on. From what I could find, the church has been called out for molesting kids and covering it up since at least as early as 1049. They’ve most likely been doing this for much longer obviously, but as far as being directly called out on it and that being documented, it’s been nearly 1000 years.
“Peter Damian (1007-1072) wrote to Pope Leo IX (1048-1054) about the cancer of sexual abuse that was spreading through the church: boys and adolescents were being forced and seduced into performing acts of sodomy by priests and bishops; there were problems with sexual harassment among higher clergy; and many members of the clergy were keeping concubines.” via: https://www.americamagazine.org/issue/534/article/11th-century-scandal
Peter Damian also wrote the Liber Gomorrhianus circa AD 1050-1051. From wikipedia:
“He was especially indignant about priests having sexual relationships with adolescent boys. He singles out superiors who, due to excessive and misplaced piety, have been lax in their duty to uphold church discipline. He opposes the ordination of those who engage in homosexual sex and wants those already ordained dismissed from Holy Orders. Those who misuse the sacraments to defile boys are treated with particular contempt.”
I haven’t experienced that, but I used to do my amazon purchases at the end of the month until I noticed all the prices get raised around that time. So now I shop without rhythm to not attract the price inflation worm