• by David Goetzl  @dgoetzl, August 14, 2008

Using a research tool it developed, NBC Universal released figures Wednesday showing widespread consumption of the Olympics across multiple properties. Television was the dominant medium--some 107 million people tuned in Sunday--but visits to NBCOlympics.com and viewing on mobile devices have been climbing daily.

NBCU is using a Total Audience Measurement Index (TAMI) to try and determine the reach of its coverage--across TV, online, mobile and VOD. On Sunday and Monday, the TAMI figure came in at well over 100 million.

On Sunday (the night of the thrilling finish in a swimming relay involving Michael Phelps), the TAMI was 113 million. Here's how it was calculated: More than 107 million people watched at least six minutes of coverage on one or more of the NBCU TV networks. In addition, 5 million people visited NBC's Olympics Web site, 495,000 tuned in on mobile, and 28,000 watched on VOD.

The 113 million is not unduplicated--meaning that some people may use more than one medium. But from NBCU's perspective, the upside is the opportunity to expose people to more--and different--types of advertising.

On Monday, where there was an hour less of prime-time coverage, the TAMI came in at 103 million.

The TAMI uses different measurement services for the various media. For example, it employs Rentrak for VOD and Nielsen for TV.

NBCU has no plans to use the TAMI as an ad sales currency, partly because it uses so many different metrics. But the network hopes it will serve as fodder for advertisers looking for a sense of how many people consume particular content across multiple touchpoints.

NBCU says it expects to employ the tool in the fall as a gauge for total consumption of some of its non-Olympics properties. "Sunday Night Football," which will be simulcast live on the Web, seems to be a candidate. So would Notre Dame football, where games were simulcast on mobile last fall. A slew of NBC prime-time shows are also available on-demand on the Web.

For the Olympics, unique users of both NBCOlympics.com and the Games' mobile coverage have risen each day. On Friday, the day of the Opening Ceremonies, there were 4.2 million online visitors, according to NBCU figures. The number of online viewers rose to 7.8 million on Monday. On Friday there were 210,000 mobile viewers; that number had risen to 476,000 on Monday.

The figures for VOD viewership are more modest, but NBCU says the platform is still in its infancy. Some 34,000 people tuned in Friday; that number jumped to 53,000 Saturday before dropping to 28,000 on Sunday.