CPM means ‘Cost Per Thousand Impressions’. It’s what advertisers sometimes use to judge how expensive a campaign is relative to the number of subscribers you have.  To calculate how many thousand impressions are in your list, divide the total number of subscribers by 1,000.  For example, if you send a newsletter to ten thousand people, you have ten thousand impressions’ (10,000 / 1000 = 10). Your total sponsorship fee divided by the number of ten…