Broadcast and cable stations donated an average of 17 seconds an hour to PSAs, totaling one-half of one percent of all TV airtime, according to the study, Shouting to be Heard (2): Public Service Advertising in a Changing Television World, released by the Kaiser Family Foundation. The most frequent time period for PSAs to air was between midnight and 6 a.m., accounting for 46% of donated PSAs across all stations in the study; looking only at broadcast stations, 60% of donated PSAs ran overnight. The time period with the fewest donated PSAs was during prime time (8-11 p.m.), with 13% of all donated PSAs.

The report was released on Thursday, January 24, 2008, at a forum that featured Federal Communications Commission Members Michael Copps, Jonathan Adelstein, and Deborah Taylor Tate along with representatives from News Corporation, CBS, Time Warner, Univision, the Ad Council and the American Legacy Foundation.

 Report (.pdf)