Ok So... That was fun for about 30 seconds...

if you giveaway a game that is later bundled i believe your CV is adjusted

CV can change when you GA a newly bundled game. It sometimes takes a while before the 15% multiplier happens.
I'm sure there are other reasons that others can think of.

[Edit: Ninjad!]

The levels are given by the number of users that are at a certain level at a certain point.
If somebody else(or more that just one person for that matter) finished a giveaway just after you got to 6.00 they replaced you and your level dropped just a bit. The basics are that you have to keep giving away so you can keep your level.

Site doesn't store prices of games at time of giveaway unless they're removed from store. So if some game gets price drop, your contribution drops as well. Plus bundles are added manually and retroactively.

From the giveaways you made I can only assume it's because Silent Hill Homecoming has been added to the bundle list on 19th March 2015, so it applied retroactively to like 3(?) of your giveaways.

Well that's really frustrating to say the least... And possibly some of the most obnoxious timing possible...
Guess I can close the case on this one then.

And hey, I got to "Enjoy" it for 30 seconds.

(Is there a way to close a topic?)

I lost a lot of CV (about .75) all at once, and was confused as to why. It wasn't that something had been bundled and it had been retroactively reduced, it was because FaeVerse Alchemy's base price on Steam had been reduced from $30 to $15! Awesome news since it means more people will (hopefully) get involved, and also nice to know exactly WHY my CV dropped! ^__^