Magic numbers

Some years ago, someone told me that the following was a well-established fact: that for every three years you'd been in a relationship, it would take you one to really move on from it. At the time I ranted like a loon, because it seemed very unfair that someone who had - as a strictly academic example, of course - been in a miserable relationship for nearly twenty years would have to wait another seven to escape completely from it.

But it's true. Dammit.

So I was thinking about numbers and trying to identify other life formulae that seem to work.

I'll get back to you on this one.