Even the traditional tune-out that happens during the second week of the Olympics shouldn’t stop NBC this year.

Since 1992, the Summer Olympics have averaged a 12.5 percent drop in viewership during their second week. Barcelona in 1992 saw the greatest drop, 16 percent, and Atlanta in 1996 saw the smallest, 9 percent. Sydney in 2000 and Athens in 2004 each saw 12 percent drops.

NBC knows and expects ratings to drop this week, but its average of a 17.2 rating through 10 nights means that even if ratings fall by 15 percent, the network will finish with a 16.1 rating average. That would put the network 11 percent ahead of its 14.5 rating guarantee to advertisers.

That’s great news for the network, which paid $894 million for rights fees and still had advertising inventory during the Games as late as last week.