Decrease in Airpush earnings

My Airpush earnings have decreased for 20-25% compared to earnings for April. What your stats say?
Are there some other ad networks that are tried out and proved to be better?

Thank you in advance

how about sharing the earnings graph for better discussion

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compared to April, the number of active users increased by a third

I have noticed similar to this also.

Since Mid June my earnings have been pretty good especially with smartwall CPM. July has been great, but keeping fingers crossed hoping this lasts.