I’m really not sure! There are no yearly totals displayed on WU. Just daily and monthly. I failed to see a yearly total in the WU downloads to PWS_Dashboard
Originally, after I updated, it was only off a a couple hundred inches. I tried running PWS_history_recreate.php. I ran it several times and the Annual Rainfall amount climbed every time. So, that may be a clue.
Wim said that: “All math is done in PWS_Dashboard.” So I’m assuming that the error is there. Not something that is wrong with PWS_Dashboard but from my ham handed attempts to fix it.
I have to say this is one of the reasons I stopped using cron/history/status: WU holds some phantom numbers that cannot be corrected. Every time an error crept in from my end and I tried to correct it, WU would reproduce its rubbish - maybe because I was doing something wrong, who knows - and I had to go back and correct that, too.
Maybe I was running PWS_history_recreate.php and I should have been running update?
But I don’t think OP has the luxury of that choice. . .