When someone says they lost 2 sizes (for example) what does that mean? This seems to be one of those things that everyone understands but me.

I mean, if you go from a 20 to a 14...
do you count 20-18-16-14, and say you lost 4 sizes? or
do you count the sizes in between - 18 and 16 - and you say you've lost 2 sizes? or
do you count the first one and the middle ones - 20-18-16 - and say 3 sizes?

You count the ones you lost. If you go from a 20 to a 14, you "lost" the sizes 20, 18, ad 16, so it's 3 sizes.

I'd call it 3

Thank you!