thanks for replay i was not focus on ? thanks for explainIf you put your mouse on ?, Bodis explain it.
However RPM or revenue per thousand impressions comes from estimated earnings and impressions that you could earn for every 1000 impressions received.
RPM means nothing if not combined with CTR (click through rate).
Assuming a 10% CTR, $3 is not so good.
However to analize a statistic, you should wait 2/4 weeks at least with those small figures.