I’ve read a ton on this forum about what can increase PR, but what kills it. Does anyone have examples from experience on things that decimated or drastically lowered their PR?
As far as I know, there are only three things... 1) The bar being raised and your site not increasing likewise 2) Links that used to point to your site no longer pointing to it 3) Being banned and going to PR0. Hope that helps.
If one of your high ranking backlinks drops their link to your site you can expect a drop in your site pr. Since page rank is the sum and quality of backlinks to a webpage I think it goes without saying that losing backlinks is the only way to drop page rank other than a manual intervention down at google.