Credit goes to suinoq and maniacgreek from Reddit. Lots of info on how they came to the numbers that they did can be found in this reddit post.
If stat values (including aim assist & zoom) are not shown it's because either the scope doesn't affect any or I don't know them.
Each weapon type has a different base zoom. The numbers you see on this site with an plus sign are additive to the weapon's base zoom.
See this amazing Reddit post by suinoq for more info on how the resulting zoom is calculated.