Time to pull an ad? Ad Rotation Experiment

Never used rotation before

[pavlovapete]

Hi,

campaign had been running for a couple of weeks.

% Served -- Clicks -- Imp -- CTR
53.44% ---- 23 ----- 171 --- 13.45%
46.56% ---- 0 ------ 149 --- 0.00%

Looks like a clear winner - but how long should I continue this test before I am "certain" which ad is performing better?

Thanks

<edit>format

[koncept]

I would normally say there haven't been enough impressions in this example to pull anything, but that 23 clicks versus 0 is pretty obvious, like you said.

pull it and write an even better one.

[pavlovapete]

pull it and write an even better one.

Sage advice koncept.

Cheers

[LucidSW]

Agree with koncept. Usually I wait for 30 or so clicks for each ad. But that 23:0 click ratio is very telling and I'd pull out the ad and test with another.