I've noticed mine has been, too. The battery section doesn't make much sense. For example, on March 3rd, my battery usage was 61%, my screen-on time was 2 hours 40 minutes, and my screen-off time was 19 hours 33 minutes. When you look at which apps made up what percentages and add them up, it comes to 16.3% (if I'm generous and round up), and when you add together all the individual values for total screen minutes with each app, it comes to 1 hour 27 minutes.