Nielsen Media Research measures audience levels using both electronic meters and diaries. The national sample is a combined sample of the “Nielsen families” using meters and diaries. It consists of about 5000 homes in 210 different television markets. The national Nielsen ratings also include key demographic information such as the number of adults ages 25–54 watching a particular show.

The highest-rated TV show as of March 2001 was the final episode of M*A*S*H, which received a rating of 60.2 and a share of 77 on February 28, 1983.

As of March 2001, 12 of the 25 highest-rated shows were Super Bowl broadcasts.

In January 2001, the average number of televisions per US household was 2.4.

About 60% of US teens have a television in their bedroom.

In 1999, the automotive industry outspent all other industries for television advertising.