According to a new report released by TDG, "Making Ad-Supported VOD Work," VOD services provided by pay TV operators should be generating significantly higher viewing and advertising revenue. That they're not suggests inadequate advertising support for VOD and awkward program guides that limit availability and viewing of ad-supported VOD content.According to TDG, as a result of pay TV operators' lack of attention to ad-supported VOD, total VOD use is small, representing only 1% of all U.S. TV viewing. TDG estimates in Q4 2011, Netflix subscribers watched 80% more streaming video hours than were viewed in the same period on all U.S. pay TV VOD.TDG says operators could increase VOD viewing and ad revenue by a factor of three or more by deploying dynamic ad insertion, better measurement technologies, and improved program guides.