How to read the result
Treat it as a ceiling, not a forecast. The number that matters is the reverse one: the pageviews you'd need for a goal. If $100 a month needs 25,000 pageviews and you have 2,000, the plan is content and search traffic for a year, not tweaking ad placement.
What I've seen on my own sites
Topic matters as much as traffic. My pregnancy and baby sites earn several times more per thousand views than my Chinese-language sites, with similar traffic, because of where the readers are and what the advertisers sell. The note on ad RPM by niche walks through the actual figures.