Cpc Fluctuation (how much is normal)

[nickys]

My earning have been down for a bit so I decided to put all of my earning on a spreadsheet since I started.

Question: Is it normal for cpc to fluctuate so much?
(amount has been changed a bit to comply with Google rules)

10 months averaging cpc of 31
10 months averaging cpc of 21
20 months averaging cpc of 40
3 months of cpc of 21


As you can imagine a change of 40 cpc to 21 cpc has basically cut my earning in half!

I'm trying to figure it out if I should get nervous that it will never go back up, or if this is normal.

Thanks!

[eek2121]

Your CPC will always fluctuate. It's based on the country, visitor, advertiser, and the direction of the wind. Attract more US/UK traffic to help with your CPC.

[piatkow]

And may vary by time of year. There may be particular ads that are seasonally related which may display and push your cpc in one direction or the other.

[jbayabas]

You're lucky your earnings were only cut in half. I worry too that it will never go up. It's been 4 months now of downward spiral.

[nickys]

Actually I should have mentioned that those times where all in a row first 10 months of 31 then 10 months of 21 ect. so it's obviously not seasonal related.