There is no "best" number for CPC and RPM, It can vary from publisher to publisher, and even site to site.
RPM is based on your estimated earnings and impressions, so that's going to vary based on those statistics, and those stats change all the time, so that means the RPM will change.
CTR should be reasonable though.
In other words, if you have 100 impressions, you don't also want to see 100, or even 25 clicks.
You might expect to see anything between 3 and 5 clicks for 100 impressions. Too much more can be heading towards the high side for CTR, but again, depends on the site and visitors.
RPM is based on your estimated earnings and impressions, so that's going to vary based on those statistics, and those stats change all the time, so that means the RPM will change.
CTR should be reasonable though.
In other words, if you have 100 impressions, you don't also want to see 100, or even 25 clicks.
You might expect to see anything between 3 and 5 clicks for 100 impressions. Too much more can be heading towards the high side for CTR, but again, depends on the site and visitors.
