Average CPC problem

Can't get it back to old levels

[graywolf]

Here is the data for three days in the begining of January where everything was working.

IMP CLK .CTR % .CPC. POS 
141 844 16.70% $0.32 2 
130 703 18.40% $0.35 2 
123 654 18.80% $0.35 2.1 

After I had to change the ad URL due to the new policy, and I hav't been able to get it back to the old levels. Here is the same ad for the past week and half.

IMP CLK .CTR % .CPC. POS 
154 907 16.90% $0.52 2.1 
103 716 14.30% $0.55 2.2 
 97 686 14.10% $0.58 2.1 
158 965 16.30% $0.55 2.1 
205 1122 18.20%$0.47 2.1 
168 1123 14.90%$0.52 2.1 
114 826 13.80% $0.53 2.1 
146 924 15.80% $0.38 2.3 
107 779 13.70% $0.53 2.2 
116 748 15.50% $0.60 2.1 

I thought things were finaly starting to stabilize and return to the old levels when my CPC went down to $0.47 and then $0.38, but it moved back up to $0.53 and then $0.60 yesterday. The max bid is set at $0.75. If I lower it I drop from the #2 spot and traffic drops to 20-30 clicks per day. So what am I doing wrong?

[inasisi]

Many of the affiliates have increased their Max CPCs to ensure that their ad shows up on Adwords. In response to that, many of the non-affiliates have also increased their Max CPCs to retain their positions.

Since you have to pay 1c more than the ad below you, your avg CPC could have risen due to these reasons.