Political campaign managers and advertising consultants spend a lot of time in meetings and on the phone talking about GRP's, or gross rating points. Since more GRP's cost more money, it's important to know a few basic facts about rating points.

• One rating point is one percent of a given population. If “Channel 5 News Alive at 10” has a Nielsen rating of 4.7 among persons 18+, it means that on average, 4.7% of everybody over 18 years old is estimated to be watching. The rating is based on the total population universe in the market, whether they are watching television or not.
  


• Gross rating points (GRP’s) refer to the sum total of all rating points in an advertising schedule.
  


• When you talk about GRP's, make sure you know what demographic group you're talking about. That can make a big difference. For example, a schedule that delivers 1000 GRP's among adults 18+ can deliver 1300 GRP's among the smaller universe of adults 35+ because older people spend more time watching television.
  


• GRP's based on demographic groups don’t directly translate into voter GRP's. Using our Target Media Index™, we can estimate how many GRP’s your campaign is achieving among Republicans, swing voters, and Democrats.