Your adsense earning depends upon following factors.Ensure that you have done following things.
1.Website Traffic – You Should have decent website traffic.
Your website traffic depends upon unique content,SEO,promoting your website.
2.Google Adsense techniques – How you are integrating adsense
3. Ad Placement – Where you are placing the ads?
It depends upon your website design.Based on your website you should use ads because some website vertical ads will be suitable and some websites horizontal ads will be suitable.
4.High Paying Keywords – Keywords Research
Find high paying keywords
Check High Paying Keyword List here.
5. Blend Your Adsense Ad – Do Experiment
1.Below Post title
2.Header Position.
3.Linkbar – Link Units
4.Color.