How do you determine deck clearance in an engine using math?

When the goal is to be between 9.0 and 9.5, there is room for some variance. I'm not referring to bearing clearance here where a rod with .008 will rattle and one at .002. runs quiet.
A few thousandths difference in deck height will not make a POINT in compression. By a few, I mean less than 10.
A few CCs in combustion chamber volume will.