Rio Olympics 2016: Opening Ceremony TV Ratings Fall 28 Percent From London

Fireworks explode over the Maracana Stadium during the opening ceremony of the Rio 2016 Olympic Games on Aug. 5, 2016 in Rio de Janeiro, Brazil. 

Chris McGrath/Getty Images

They were bound to be big -- but the Olympic ratings did not start out as NBC has grown accustomed to for a Summer Games.

The 2016 Summer Olympics kicked off in Rio de Janeiro on Friday night (Aug. 5), airing (almost) live on NBC in much of the United States. Early returns give the broadcast network's coverage an overnight 16.5 rating among households. That should likely translate to somewhere in the vicinity of 30 million viewers -- putting it well south of the 23.0 overnight rating from the most recent Summer Games in London. It stands as the lowest overnight for a Summer Games since 1996.

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The swirl of controversy around housing, polluted water and generally rough times in the Brazilian metropolis dominated the conversation in the run-up to the games, not unlike the Sochi scandals in 2014, but there were few worries of it dampening ratings. If Rio's opening ceremony had anything working against it, it was the lack of spectacle that the cash-strapped South American country would be able to put on. Beijing and London set a very high bar for theatricality during the last two Summer Olympics.

Working against the ratings draw was also the earlier go-time for the U.S. Olympic Team during the Parade of Nations. That came an hour earlier than in London. Ratings peaked at a 19.0 overnight between 10 and 10:15 p.m., when the U.S. team walked.

Down as though they might be, the Olympics are still quite massive. In the primetime hours between 8 and 11 p.m., the coverage averaged a 10.0 rating in the advertiser-favored demo of adults 18-49.

Even more so than its Winter counterpart, the Summer Olympics are ratings pay dirt. The 2012 Summer Games in London were the most-watched event in U.S. TV history, pulling in 219 million American viewers over the two-plus weeks of coverage. That number included an average primetime audience of 31.1 million viewers, an astounding feat considering contemporary viewing habits. All told, 2012 was also the most-watched non-U.S.-hosted Olympics since the landmark 1976 Montreal Games.

Opening ceremony ratings often set the tone for Olympic coverage. Night one of the 2012 Olympics soared to an all-time Summer Games high -- a 20.0 rating among households and 40.7 million viewers. The only kick-off to pull a higher number in recent history, thanks the domestic venue, was Salt Lake City's 2002 Winter Olympics. That opening ceremonies took a 25.5 rating and 45.6 million viewers.

Opening Ceremony of the Rio Olympics 2016

Understandably, there's been a lot of speculation about how streaming will affect NBC's pull with viewers on the linear channel this Olympics. Not only is there more streaming available, the lack of a significant delay (thanks, Brasilia Standard Time) will likely compel more of the West Coast to find alternative ways of watching events as they happen. NBC, which has the Olympics on lock through at least 2032, did not have a difficult time wooing advertisers. The Rio Olympics are pulling in an estimated $1.2 billion to the Comcast-owned network.

Updates will arrive later -- as will 16 more days' worth of ratings. In the meantime, here's a look at how the last eight Olympic opening ceremonies have performed, in final household ratings and total viewers, since NBC took over the broadcast contract.

2014: Sochi Winter Games -- 17 rating; 31.7 million viewers

2012: London Summer Games -- 21.7 rating; 40.7 million viewers

2010: Vancouver Winter Games -- 17.3 rating; 32.7 million viewers

2008: Beijing Summer Games -- 18.8 rating; 34.9 million viewers

2006: Turin Winter Games -- 12.8 rating; 22.2 million viewers

2004: Athens Summer Games -- 14.4 rating; 25.4 million viewers

2002: Salt Lake City Winter Games -- 25.5 rating; 25.5 million viewers

2000: Sydney Summer Games -- 16.2 rating; 16.2 million viewers

This article originally appeared in THR.com.