Does creating new ads affect CTR/CPC?

Trying to figure out what happened

[limitup]

Does anyone know for sure if creating new ads affects your CTR/CPC? For example if I have a keyword with a 5% CTR when run under a certain ad, if I go ahead and create another ad (so now there are 2 ads rotating) does this affect the CPC I pay for this keyword?

Our CPCs have literally doubled in the past few weeks and I'm trying to figure out why. I know most of the top 5 sites that I'm bidding against and no one has significantly raised their max bids recently.

[nyet]

The new ad could change your CPC if the new ad's CTR is different form the old ad's.

If the CTR on that word is much lower than with the old ad, it can upset the apple cart.

Sometimes a new ad will help your adgroup CTR but for some words the CTR might decrease.

Now <i>how</i> do you know none of your competition are increasing their bids?

[limitup]

Well maybe this explains it then. I've been split-testing a bunch of new ads over the past 1-2 weeks, but my new ads always do worse than my existing ad. So that could be the reason I guess? I keep trying to improve on my existing ad but it seems like I can't, so I should probably stop trying.

I don't know 100% that no one has raised bids, but I'm 99% confident. I speak to all the top bidders on a regular basis and everyone says they have not. I believe them as we are all on good terms and no one has a reason to lie.