NBC’s Olympics ratings faced a steep decline in Tokyo.

According to Front Office Sports, the Tokyo Olympics drew the lowest Summer Olympics audience ever, averaging just 15.5 million primetime viewers. That’s down 42 percent from the Rio Olympics in 2016.

Some of the challenges cited by NBC included the COVID-19 pandemic, the Olympics’ postponement and the difficulties faced with the time differences.

NBC paid $1.1 billion for Tokyo 2020 rights and owns U.S. media rights to the Olympics through 2032.