Conversion bid metric
Our Average CPC shot up by as much as 40%. (60% for some campaigns) when we updated our Conversion bid metric under "conversion settings". Could anyone please explain this.
Re: Conversion bid metric
To make it clear, changing the conversion settings for Conversion bid metric (https://support.google.com/adwords/answer/3438531?hl=en) is not going to change how the ad auction or ECPC works. It will only affect how the conversions are measured depending upon whether you have selected unique or multiple conversion to add up.
As per the help center notes, in case of ECPC (https://support.google.com/adwords/answer/2464964?hl=en), your max CPC bid can go higher by 30% (max) and can go lower as well by 30%. Make sure you don't have any other advanced settings turned on like bid multipliers or any automated rules/scripts to increase the max CPC.