After 1 week of observation, my CTR and CPC has dramatically increased after I inserted adsense code in my wordpress post. My CTR for the past couple of months was averaging 3% daily and CPC was ranging from $0.35 to $1.02. I analyzed my one week result and CPC has dramatically increased to minimum of $0.5 and upto $3.50 per click.. Today, I got 2 clicks with $2 each. My CTR has increased to $5.7% average... Here is my new placement that did it.. see the blending of colors..
Placement can affect CPC because the ads will show only keywords from inside post if this is the case... not the keywords of the whole page.