NEW YORK: The number of ads viewed "post live" by DVR owners in the US is much smaller than many marketers think, new research from MPG has indicated.

According to the media agency's figures, 91% of total ad views among 18-to-49-year-olds were "watched live", with the remaining 9% coming via DVR playback.

MPG analysed the first 11 weeks of the 2009/10 promotional season, as recorded by C3 data from research firm Nielsen, for its report.

If ad views are recorded on the basis of programme rating averages, as is generally the case, the data suggests that around 46% of ads are watched via playback.

However, MPG discovered a much lower DVR viewership by measuring ratings of individual commercials during the 11-week period.

This in turn suggests that viewers have become used to skipping commercials when watching TV shows in playback.

Don Seaman, director of communications analysis at the agency, said: "What this tells us is that the vast majority of commercial viewing is live ... And the pattern holds true across different genres, networks and days of the week.

"We have a responsibility to our clients to make sure they're getting the entire picture, and the way the industry is positioning C3 doesn't accurately portray what's happening with time-shifting."

MPG's figures also revealed that all four of the major US networks - NBC, ABC, CBS and Fox - had a DVR ad viewership of around 10%.

However, some shows had much higher ad "stickiness", with 25% of ad views for Dollhouse, shown on Fox, coming from DVR playback.

This figure stood at 24% for The Office and 23% for Heroes, both on NBC.

DVR-style devices are currently in 36% of TV-owning US households.

Data sourced from Media Week/Nielsen; additional content by Warc staff.