About a month ago, we reported that AdSense reports were not sorting properly.
On my "Overview" screen, when I click on "Top Channels" it is not sorting by "Earnings" as usual. I can't detect a sort field by the data presented, it seems either to be unsorted or sorted by channel-id or some other hidden field.
A Google representative confirmed the issue and said they are working on it. One month later, it is now finally fixed.
I guess it wasn't a huge priority for Google to fix those reports. AdSense publishers are elated the reports are fixed.