The ratings for the Summer Olympics in Rio are way down from the London Games in 2012

The Summer Olympics in Rio got off to a rough start, as it had the lowest-rated opening ceremony in a quarter century.

According to Nielsen's live-plus-same-day data (via Ad Age), NBC's tape-delayed broadcast received a 13.9 household rating. That's the lowest viewership since the Barcelona Games in 1992 had a 13.8 rating.

The Rio opening was down 36% from the London Games in 2012, and didn't even top the biggest summer sports draw in the US of this year, a title still held by Game 7 of the NBA Finals, which had 31 million viewers (the Rio opening had 26.5 million).

The slow start for the games continued on Saturday, when the 20.7 million viewership was down 28% from the first Saturday of the London Games.

But hopefully when numbers come in for Sunday, there will be an improvement. That was the first night US swimmer Michael Phelps hit the pool and won the 19th gold medal of his career while participating in the 4x100 relay.

NOW WATCH: The directors of 'Catfish' and 'Nerve' reveal how to make it in Hollywood without going to film school

Please enable Javascript to watch this video