I would say it depends on your proportions. some say the button should be at the mid-point between the top of their head and the floor. Some people say at the belly button, some people say an inch above the belly button. It depends on your body, how you want it to feel and what looks good on you. Generally, higher buttons around the solar plexus is a fashion thing. Very "in" right now along with shorter hems. If you want something more timeless go down a bit.