Olympic broadcast revenues reached $4.1 billion from 2013 to 2016, a 7.1 per cent increase from the previous four years, according to the International Olympic Committee (IOC).

The sale of broadcasting rights provides the IOC with 74 percent of its revenue, which it then distributes to national organizing committees and international sports federations to support athletes.

By by the end of the Rio Olympics about half the world's population will have watched the Games in some way as gains in internet delivery of the event have outpaced viewing on traditional channels, Timo Lumme, managing director of IOC Television and Marketing Services, told reporters on Wednesday.

"The footprint of the potential reach of the Games is increasing," Lumme added.

Lumme's projection was in line with viewership from the last summer Olympics in 2012. The IOC found that 3.6 billion people around the world watched at least one minute of the London Games. The world's population is roughly 7 billion.

Viewers' habits change during every edition of the Games, with more searching for Olympics news online or through social media, fragmenting the traditional broadcast audiences that advertisers still pay a premium for.

Lumme said ratings in the Americas thanks to a favourable time difference have been strong, as well as in Brazil. Globo TV, the main Brazilian rights holder, had its highest ratings since the World Cup in 2014, Lumme said.

When asked about ratings being down in the US compared to London on NBC's main broadcast channel, he said that ratings are on par with London if all of the platforms viewers are watching are combined, such as cable and online.

"People are just consuming the Games differently now," Lumme said.

He noted that NBC viewers had already watched 2 billion streaming minutes, more than the streaming activity of the five previous Olympics combined.

The IOC is also close to launching its $450 million Olympics television channel, which will go live on the last day of this year's Rio de Janeiro games. It is aimed at keeping the Games in the public eye in the two-year period between the summer and winter Olympics and winning over a new generation of younger fans. – Reuters