Blue percentage bar on upper left hand corner of new BLADE 15

I noticed a small percentage bar that showed up on the upper left hand corner of my screen. It has a black border, blue bar that displays 100 on the bottom. I can move the white cursor at the top of the blue bar and the number decreases but goes right back up. I can't seem to delete it. Does anyone know what this is and/or how to remove it? Thanks! Bill