App store download number error?

Why your total downloads aren't updating in months is very odd, but I think it's a unique error. Is the "66150" also dropping?

The way I understand it:

The "total downloads" and summary numbers in general are different things. The main number users see is the number of unique downloads (different users). If the same user downloads for multiple devices, that number only goes up by 1, and not the number of devices. (I've seen that when I have an app in "pending" mode and installed it on a couple of watches).

Also, consider the case where you have 100 downloads, and then you update your app, and all 100 users download the update. That number will stay at 100, but in the summary, you'll see a spike of 100 downloads. (the total there will be 200 or more)

The summary is what's used for the "most popular" ranking. When you update an app, you get moved to the end of that list, but as the downloads in the summary (including users just getting the update) goes up, the app's ranking moves up. Consider some of the apps that live in the top 10. If one of them gets an update, it gets moved to the back of the list, but with the number of users getting the update, they move back up very quickly. "average stars" may also come into play here. I also think there is a "time period" involved, and the ranking is based on something like the last few weeks.