I’m still not sure exactly how NBC is tabulating these ratings, but either way, they were huge for Phelps’ run at eight on Saturday night. Not only did it crush any other Sport the network has aired, it was the highest Saturday rating since Empty Nest debuted back in 1990. Via Yahoo….

The telecast averaged 31.1 million U.S. viewers, NBC’s biggest audience for a Saturday night program since an episode of “The Golden Girls” spinoff “Empty Nest” drew 31.4 million viewers in February 1990, according to Nielsen Media Research data cited by the network.

It was the culmination of an especially dramatic day of Olympic competition, which also saw Phelps’ U.S. teammate Dara Torres, 41, lose the women’s 50-meter freestyle by a 1/100th of a second to 24-year-old Britta Steffen of Germany. Torres, the oldest U.S. swimmer, ended up with three silver medals.

Jamaican sprinter Usain Bolt grabbed gold in the 100-meter dash after the reigning world champion Tyson Gay of the United States, who suffered a hamstring injury six weeks ago, was eliminated in the semi-finals.

But the dramatic story arc of Phelps, who came away with gold medals in all eight events he competed in, has been the biggest draw for NBC’s Olympic coverage.

The network has averaged 30 million viewers in prime time — on par with the numbers tuning in for “American Idol” — since the games opened on August 15, and Saturday night’s audience peaked at 40 million viewers in the half hour during which the men’s 400-meter medley was held.

Through nine days, 191 million viewers have tuned in to at least one six-minute bloc of the Beijing Games on NBC and its various sister cable networks — 14 million more than for the Athens Games and 5 million more than the Atlanta Games over the same period, NBC said.

First of all, that’s just an insanely large amount of people. To put things into comparison, last year’s Super Bowl pulled a 43.2 and the only American Idol to ever beat that figure was the Season Two finale (Ruben Studdard won).

Second, 31.4 million people watched Empty Nest?!?! I never knew the Golden Girls spinoff was that popular. RIP Estelle Getty.

Phelps’ Olympic feat lifts NBC to 18-year record (Yahoo)