There is no proper answer for this bro, it depends on several factors, to be honest.
It usually depends on the kind of ads that are displayed on your website, there will be an ad auction (Google AdWords) and advertisers are selected by this. Also, not to forget, your earnings are reflected by the kind of content you publish. But still, there is a small formula for RPM, which stands for "Revenue per thousand impressions".
RPM = (Estimated earnings / Number of page views) x 1000