“Gross ratings points” is a term is rarely encountered by lay people but used universally by media buyers because it measures advertising impact across markets in a uniform way, regardless of how cheap or expensive ads actually are. In the pricey New York City media market, for instance, $1 million spent on TV won’t go nearly as far as it would in, say, Pittsburgh, where advertising is much more affordable.

GRPs solve that problem by gauging how many times, on average, members of your target audience have seen your ad, with one GRP equal to 1% of the audience watching an ad one time. In this case, where the buy is for 2,000 GRPs, a buyer might say that 100% of the audience has watched this spot 20 times, though of course it could also mean that 50% has seen it 40 times.

An old rule of thumb holds that a message advertised on broadcast television has reached saturation levels at 1,000 GRPs—in other words, when 100% of your audience has seen it 10 times. But in the modern multi-platform media landscape, abetted by the rise of DVRs, that number has crept ever higher, though there's no universal agreement about what constitutes saturation nowadays. Still, the 2,000 GRPs that Medium says Rispone’s buy is worth will almost certainly reach his entire intended TV audience.

Bear in mind, though, that these figures only take into account Rispone’s spending on television. To connect with its complete universe of targeted voters, a modern campaign must advertise on other media (including radio and online) and contact voters directly (by means such as mail or door-knocking).

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