Do different size ad pay differently?

[Raymond]

I have been wanting to get rid of a big 336 X 280 ad and change it to a 468x60 on one of my dynamic page. I tried it one day and the earning per click dropped by a really significant percentage. Because this ad spot is one of my main source of revenue I had to switch it back to the 336 X 280.

My question is, do different size ad have different payout(per click wise)? For my case the EPC dropped over 50% after I switch to a 468.

[ken_b]

The difference is probably that the 468x60 adblock holds 2 ads at most but the 336x280 holds a max of 4 ads, so there may be more likelihood of getting a click.

It may also be that the 336x280 adblock is more popular with advertisers doing targeted ads so they may be willing to pay more for those spots.