CPM airpush USA

Someone knows which is CPM (push and smartwall) with USA traffic?

I have an app where most of the traffic comes from USA, here are the cpm per ad type:

Smartwall: $4.39
Push: $2.19
Icon: $2.49

I have two apps where most my traffic is coming from USA. I don’t have icons enabled. CPM has been solid for me for past month, especially smartwall.

Smartwall - $2.65
Push - $2.21

I’m pretty new at the monetization of my apps. Just finished my first not too long ago. it will be really educational for me to know the answers to this question. Been considering a couple of ad networks so will see what CPM i can get