Source: Nielsen
More results (Tweets, Unique Authors, and Impressions) can be found in the attached spreadsheet.
Activity metrics (Unique Authors and Tweets) are a measure of relevant Twitter activity from three hours before, during and three hours after an episode’s initial broadcast, local time. Reach metrics (Unique Audience and Impressions) measure the audience of relevant Tweets ascribed to an episode from when the Tweets are sent until the end of the broadcast day at 5am. The data includes new/live primetime and late fringe episodes only and excludes sports events. Nielsen Twitter TV Ratings are only available for English-language U.S. Broadcast and Cable Networks.
Tweets – Tweets ascribed to a linear TV episode.
Unique Authors – Unique Twitter accounts that have sent at least one Tweet ascribed to a specific TV episode.
Impressions – The number of times any Tweets ascribed to a TV episode were seen.
Unique Audience – The total number of distinct Twitter accounts accruing at least one impression of one or more different Tweets ascribed to a TV episode.