I think one day soon that 70% parking is going to disappear.  We take that 70% for granted.  When the 70% drops to 40%, you will wish you had parked some at 70%.  As the monthly % quickly drops, if price continues to rise, you will have coins locked in 12% monthly when the yearly drops, and you will have missed your window.  So please realize that when you say "monthly is the best option" you really mean "monthly is the best option at the moment" but I doubt that is the long term truth.  There was a time when daily was the best option, and there was a time weekly was the best option. 

just 2 cents