Fast National ratings for Sunday, August 5, 2012.
 
Despite big moments like McKayla Maroney's attempt at a vaulting gold and Usain Bolt's quest to repeat as World's Fastest Man, Sunday's Olympics coverage took a big dip over last Sunday's telecast, while still dominating for NBC.
 
The network didn't help matters by airing Bolt's victory outside of primetime (the semifinal sprints were in primetime) and putting Maroney's vaulting well into the 10 p.m. hour. 
 
For the night, NBC averaged a 9.3 rating among adults 18-49, easily tops in the key demographic. In fact, NBC tripled the combined totals for FOX (1.2 rating), CBS (1.1 rating) and ABC (0.8 rating) in the key demo.
 
Overall, NBC averaged an estimated 29.22 million viewers and a 16.5 rating/27 share for Sunday night. CBS was a distant second with a 3.0/5 and 4.63 million viewers, beating ABC's 1.9/3 and 3.18 million viewers. FOX averaged a 1.6/3 and 2.71 million viewers to trail.
 
7 p.m. - The first hour of NBC's Olympics telecast averaged 20.47 million viewers and a 5.9 rating among adults 18-49. CBS was far back in second with 6.53 million viewers and a 1.0 key demo rating for "60 Minutes." ABC's repeat of "America's Funniest Home Videos" averaged 3.875 million viewers and a 0.9 key demo rating for third, topping the 1.65 million viewers and 0.7 key demo rating for FOX's repeats of "American Dad" and "The Cleveland Show."
 
8 p.m. - NBC's Olympics coverage rose to 28.27 million viewers and an 8.5 rating among adults 18-49 for the 8 p.m. hour. CBS stayed in second with 5.85 million viewers and a 2.1 key demo rating for "Big Brother," which improved on its numbers from last Sunday. ABC's "Secret Millionaire" averaged 3.82 million viewers for third and a 0.8 key demo rating for fourth. FOX's two repeats of "The Simpsons" finished third in the key demo with a 1.4 rating and fourth overall with 3.12 million viewers.
 
9 p.m. - The third primetime hours of Olympics coverage on NBC went up to 33.22 million viewers and a 10.7 rating among adults 18-49 to dominate the 9 p.m. hour. FOX's repeats of "Family Guy" finished second with 3.37 million viewers and a 1.6 key demo rating. CBS' repeat of "Hawaii Five-0" was third overall with 2.88 million viewers and fourth with a 0.5 key demo rating. ABC's "Extreme Makeover: Weight Loss Edition" averaged 2.55 million viewers and a 0.7 key demo rating. 
 
10 p.m. - In the 10 p.m. hour, NBC's Olympics telecast averaged 34.92 million viewers and a 12.1 rating among adults 18-49. CBS' repeat of "The Mentalist" was second with 3.28 million viewers and third with a 0.6 key demo rating. ABC's "Extreme Makeover: Weight Loss Edition" averaged 2.46 million viewers and a 0.8 key demo rating.
 
All ratings information comes from preliminary Fast National Nielsen data, which includes live and same-day DVR viewing. All numbers are subject to change.