App size evaluation / compression ratio

[#1]

Hi guys,

I'm looking for the formula to evaluate the QVW size on the disk. I saw it at one point but no way to find it back :S

So far I have got : [QVW size] =  [Source Data Size] * (1- [Compression Ratio])

Any one knows how to calculate the Compression Ratio?

I know it's something related with number of rows and distinct values.

Cheers,

Eva