TV and radio have two standard ways of presenting audience — as a whole number and as a percent of a market’s population. The first is gross impressions, which is used in CPM; the second is gross rating points, which produces cost-per-point.
The recent industry proposal, that spot media make things easier by switching from a cost-per-point to a cost-per-thousand currency measure, ignores important differences-and has competitive implications well beyond the numbers game.
