Nielsen is developing a new metric for entertainment marketers that measures the social impact of a television commercial. The “tweets per impression” (TPI) measurement shows just how effective the impression of a commercial may have been by mapping the number of tweets about the commercial shortly after it airs. TPI provides entertainment marketers a way to make sure that they are getting the biggest bang for their buck. Studios, networks and advertisers are showing interest in the new metric.

Nielsen is planning to spend a lot more time focusing on the social metric, according to Variety. The company has already begun pitching it to movie studios and TV networks. Studios can use TPI to strategize their TV advertising while networks can use it to adjust their own on-air promotions.

Many marketers want to target the viewers that will engage with the brand. Erika Faust, VP of client services at Nielsen, says 20 million people posted Tweets about brands in the last six months. That totals about 335 million tweets about brands.

TPI is still in development, but some companies are already using it to measure their social impact.