Counting DVRs.

Digital video recorders are changing more than the way people watch television. They're now changing the way ratings are tracked, too.

Nielsen Media Research is breaking out television ratings for shows recorded and played back on DVRs, rather than just live television views. The new ratings system started on Dec. 26.

The decision is drawing applause from El Segundo-based DirecTV Group Inc., which offers TiVo recorders, as well as its own branded DVR. "This will give us a lot more insight into the viewing habits of DirecTV customers," said spokesman Robert Mercer.

Nielsen engineers have been working on the technology, called an active/passive meter, for several years, at the request of clients who want specific information on program playback, said Karen Gyimesi, Nielsen's vice president of communications.

The new device is an attachment compatible with Nielsen's Local People Meters and tracks DVR playback through codes embedded in each program. The device is now in 9,000 homes, although only 60 of the homes in the sample have DVRs, Gyimesi said.

It may be some time before the ratings have a big impact, because few television watchers use the recorders. DVR penetration in the United States is relatively low--about 7 percent right now--although satellite and cable companies are offering the recorders to customers.

Still, the decision to track DVR viewership will likely affect how television networks negotiate the sale of advertising time. No matter the time slot, shows with a high rate of record-and-replay could command top dollar for commercial airtime--though the issue of viewers skipping ads is significant.

"It adds a wildcard factor to advertising negotiations," said Paul Mandabach, a principal at the Winner & Mandabach consultancy. "Right now I don't know as a buyer if I would purchase ads on the highly-played DVR shows, no matter how many playbacks they get, until ... I can see research on whether people are fast-forwarding through ads."

Nielsen expects to expand the number of digital recorders tracked in the ratings sample by 100 homes each week until the percentage of DVRs measured by the company matches that in the general population.

Staff reporter Anne Riley-Katz can be reached at [phone], ext. 230, or at [e-mail].