Putting below Header Google adsense placement to the test

Oct 27 moved Large rect Adsense unit from below post on Contests 4 Canada to below header.
Before moving Adsense unit these were the stats for this unit:Sept 26 to Oct 26

$42.14 Estimated earnings 4,596 Page views 98 Clicks 2.13% Page CTR $0.43 CPC $9.17 Page RPM

Oct.27th to Oct 30th These were the stats

$10.27 Estimated earnings

363 Page views

25 Clicks

6.89% Page CTR

$0.41 CPC

$28.28 Page RPM

I then realized I should have changed the custom channel description. and changed it.
Now to examine what will happen between Oct 27 and Nov 27