"Web Activities" chart in monthly report is not accurate

In the monthly report email, the "Web Activities" chart is bogus. It consistently packs massive amounts of data in the first date range and then has almost nothing for the rest of the month. The child's real usage is consistent across the month, so this chart can't be correct.

In the attached example, you can see almost 8000 visits for the first column (1st to 6th). Then it drops to almost zero for the other weeks. But if you look at the "Monthly Time Usage" chart, you'll see that usage is fairly consistent across the month. That is, the two charts should have some correlation, but the "Web Activities" is ridiculously wrong.