graphs

Hi, Can someone explain what the lighter green bars mean on the battery level graph? I’ve circled it in the photo. Thanks.

Is there a 'Numbers Guru' out there to take me through a basic first time set up. All I want to do is 1/a small spread sheet. with twelve rows (months) and weight in pounds in second column. 2/ a graph (or American Chart) with 'x' for weight between 150lb & 220lb against 'y' twelve (months)...