Depends on the kind of work you do and the competition. A former employer was really desperate for pretty journeyman-level Django Dev help a few years ago and for some reason it was just super tight. Ended up paying more like 350% after looking a few weeks. We obviously weren't going to hire someone at that rate for a 6 month contract but for short term help? Sure.
Well, sure...there's always a one-off where you have to throw out the rulebook on salary. But any HR team worthy of the name can still compute the actual overhead on that base pretty much to the dollar.
