As it has been pointed out in previous comments, some people are powering back up some or all each week, while others have various expenses related to their contributions to the platform. Many of the largest accounts on this list have been powering down since I joined almost a year ago... it means very little without context.

My power down, for example, is for 13 mvests. I power down 1 mvest a week this way, which allows me to basically tread water even as I power down. I'm lucky to have had some decent posting rewards since starting, and I'm roughly where I was at the beginning.

I might reduce the rate of my power down at some point in the near future, in order to be able to hold my ground when I'm not blessed with the rewards I recently received.