Ditto, how often does John Edward say, “I’m hearing a voice … it’s from someone named, named Edgar … he says … he says, ‘STOP BOTHERING ME YOU SCREECHING HARPY, I NEVER LOVED YOU, AND BY THE WAY I FUCKED YOUR SISTER.’ Does this sound familiar to anyone?”
Probably about as often as fortune tellers in the US tell people that they aren’t going to meet a tall dark stranger and will die miserable and alone. 
Or what Cervaise said . . .
It depends much on the quality of soil. Just last month a cemetary was disaffected in Zurich, Switzerland. Bodies interred 30 years ago in clay soil weren’t completely decomposed.
I read lots of murder / detective type stories and they always dig up the grave. If they moved the bones they wouldn’t be able to find the person and prove the lady did poison her husband 30 years ago
Am I the only one here who gets a kick out of someone named PoorYorick posting to this thread? Or, for that matter, someone named Roach writing a book about decomposition?
I was hoping that Poor Yorick would make an appearance in this thread! 
I once read that human skeletons (for medical schools) are prepared (in India) by placing a cadaver on an ant hill.
The ants strip the bones quite efficiently