It could be a freak of nature, the pull of gravity, the shifting of teutonic plates, the changing of the seasons (welcome to Autumn by the way, officially started at 21.02hr today), it may have been a sign from God or the threat of nuclear war that has caused this Uri Geller inspired curve to the post, my own theory is some fat lass out on the razz attempting a bit of pole dancing!
Who knows, have a great weekend.