Ha ha ha! You OLD farts humor me. That's like asking Trump how many people attend his rallies! Those 80+% accuracy rates come from .... wait for it ... the almanac publisher itself.
In 2008, the Almanac stated that the earth had entered a global cooling period that would probably last decades. I hope that's true, just because I'd like to see Al Gore and his ilk squirm a little.
From Wiki:
All that aside, I guess it could be a fun thing ... kinda like Gypsy palm readers, soothsayers and clairvoyants ... or in the south, you could always read tea leaves.Accuracy
A number of analyses have concluded that the forecasts in The Old Farmer's Almanac are not very accurate. For example, USA Today states that "according to numerous media analyses neither the Old Farmer's Almanac nor the Farmers' Almanac gets it right. "John Walsh at the University of Illinois reviewed five years of monthly forecasts and found 50.7% of the temperature forecasts and 51.9% of precipitation forecasts were in the correct direction, whereas a randomly generated forecast would be correct 50% of the time.
In its bicentennial edition, the Almanac stated, "neither we nor anyone else has as yet gained sufficient insight into the mysteries of the universe to predict weather with anything resembling total accuracy."
Here's a pretty decent article from a few years back.
https://www.cnn.com/2016/08/15/healt...acy/index.html