It is important to get the stats right about your earnings either its adsense or affiliate marketing. You should know your basic and important stats like what is your EPC for the ads, EPM (earnings per mille) if using adsense. Conversion rates if you promote affiliate products etc.
Below is my stats from adsense for last 30 days. I found the EPC ($0.21) to be okay but the CTR is pathetic.
Disclosing CTR is against adsense terms and hence its masked. The EPM is also less $2.27 to expected $4-$5, its because it comprises of several niches from non buyers to saving money niche.
Im now testing by replacing major adsense ads to amazon ads, im interested to see how Amazon ad converts. If that testing goes well ill update the stats from Amazon as well.
The best practise is to keep testing different affiliate networks from adsense, amazon, google affiliate network, linkshare, cj, share a sale etc and see which one works best for your traffic and optimize the same. Do not settle with one method of earning without trying out others.
all the best..