How to Subjugate your neighbours

[Saxon]

Can anyone tell me what sort of criteria are needed before you can get subjugation or protectorate treaty?

I remember reading that to get someone to surrender outright, you need to be ten times their size. However, I have never seen any stats on subjugation and protectorate. I assume I can go into some date file to find this out, but as I said in another thread, I am the guy they invented Windows for…

Please have mercy on your technologically challenged brethren!