How is the .5% threshold measured?

by keyword, or by keyword-ad combo

[JonBoy]

Something strange happened to me recently:
A keyword with a .7% CTR was automatically disabled (2 red stars, no email from editors) after about 1200 impressions.
Its adgroup had a mean CTR of 1%, every one of the 4 ads in the group had a CTR of at least .8%, and the keyword only occurred in this group.

So if the threshold is meant to be .5%, why was this keyword with .7% disabled?

A clue came to me today when I disabled the weaker 3 of the 4 ads in the group, replacing them with new variant of the best ad, and found my disabled keyword was suddenly reactivated.

All I can guess is that CTR per keyword is measured for each ad in the group, and has to be above .5% for each ad, not just for average for all the ads in the group.

Has anyone else ran into this? Am I right?

[webdiversity]

The 0.5% applies to the last 1000 impressions, so it might be that your ad did well at the start but then went off the boil resulting in a CTR of less than 0.5%.

It also applies to each keyword individually, as well as the total for all the groups and campaigns.

You should try using exact match if you are using phrase match and getting ads disabled.

[gsx]

webdiversity has it:

if the last 1000 impressions of a keyword has under 0.5%, that keyword is disabled

if the whole campaign has under 0.5% for the last 1000, the whole campaign is disabled (so be careful that a few keywords do not disable the whole campaign when some are returning good ROI)

[JonBoy]

The term had received 1071 impressions and 8 clicks in it's life. It would be a miracle if these 8 clicks had all happened during the first 71 impressions and none during the next 1000.
And also, how does this idea explain why the keyword was automatically (without me doing anything, in the same original adgroup) reactivated when I deleted some ads and created new ones?

[gsx]

Changing any word or the advert reactivates all words in the campaign. They start again from a fresh start of 1000 - after all the clickthrough rate could then be very different with different words (negatives included in this) and/or different advert copy.

[bigjohnt]

Believe it or not, the Google auto-drop is a GOOD thing :-) Testing works.

[JonBoy]

Thanks for that Gsx - sounds like the best explanation to me. So changing ad copy reactivates keywords.

Does adding negative keywords to a group reactivate disabled keywords? I wasn't sure whether you implied this or not.

[chiyo]

Jon Boy- From our experience, adding or changing negative keywords does not automatically restore specific keywords that have been "starred". In fact we are trying to find our how to restore some since we now expect a better CTR after adding some common irrelevant or misleading neg words. It seems to us that these specifically outed keywords can only come back if you get an email from google that the whole campaign has been disabled due to low CTR and you make changes and restart it again.

[cagey1]

I have sometimes had stubborn keywords re-activated after deleting all the ads in the adgroup and then creating at least one new ad.