Yes, someone knows. But unfortunately, that someone is only Fair Isaac.
FICO reveals a lot of general, public information about credit scoring, but hardly ever gets into the details of how aging of specific derogs continue to impact credit score. You will never see that level of detail.
Their credit scoring algorithms are their business, and are closely guarded trade secrets, so you will never get a definitive answer to that question.
Therein lies one of the primary benefits of this site. We rely on anecdotal experiences of others experiencing similar situations, but unforrtunaly, what impacts one person does not impact another to the same degree.
FICO has at least a dozen scoring algorithms, which we on here call "buckets," which cubby-hole you into different risk analysis brackets, each having its own, separate impact for the same action or event, depending upon your "bracket." So even anecdotal experience of one cannot necessarity be transferred over ot expectations of another.
I think, at best, you can only assume that impact deteriorates with age, But some deteriorate faster than others. For example, I think it is kinda generally assumed experience on here that 30-day lates lose most of their impact after 2-3 years. Also, that 60-day lates are scored about the same as 30-day lates after approx. 2 years. But that 90+ lates (major derogs) kinda deteriorate much more slowly, and maybe linearly over their 7 year life span.
Other derogs not based on OC account reporting on your open account, such as charge-offs, collections, judgments, tax liens, repos, foreclosures, etc. are all major derogs, and their detoriation is slow.
You ask specifically about a foreclosure. All I know for sure is that the CRA reporting codes provide for a creditor to report foreclosure, so they have that information if they choose to use it in your score. I have no idea of its relative impact, importance, or rate of deterioration.
