Pausing vs Deleting an Ad Group

I am pretty new to this and have some under achieving ad groups. I am not sure if they are not doing well because I did not optimize correctly, or if they just aren't doing well, no matter how well I optimize. I would like to save the groups for try to work on them in a way that will not affect my current campaign. My question is this:

Whether I delete a group or pause it, my CTR goes up in my Campaign Summary page. However, does Google see deleted and paused ad groups the same? In order for the increased CTR to affect my ad performance, will I have to delete the ad groups I have paused?

 

Pause it if you plan on working on it again, delete if you don't.

 

Thanks Guy. So Google sees it the same and counts it the same either way?

 

I'll say with all sincerity I've never seen it make a measurable difference.

 

Okay. Thank you.