TV By the Numbers: The March Madness Continues, MLB Pops Up

The Baylor Bears and the Houston Cougars tip off to begin their Final Four semifinal game of the 2021 NCAA Men's Basketball Tournament at Lucas Oil Stadium on April 3, 2021 in Indianapolis, Indiana.
(Image credit: Brett Wilhelm/NCAA Photos via Getty Images)

This is a quick snapshot of TV by the numbers for the week of March 29 through April 4, revealing the most-watched shows and networks using glass-level data from Vizio’s Inscape, and the top shows and networks by TV ad impressions with insights via

Most-Watched Shows and Networks

Via Inscape, Vizio’s TV data product with glass-level insights from a panel of more than 17 million active and opted-in smart TVs. Data is linear, live TV only and includes all episode types (new and reruns). Rankings are by percent share duration (i.e., time spent watching).

Unsurprisingly, March Madness games captured the most watch-time for the week, accounting for 2.95% of all live, linear minutes. Meanwhile, MLB baseball, which just kicked off its season, took fourth place with 0.88% of minutes watched, and SportsCenter zoomed up the ranking into No. 7 from No. 22 the previous week. Other shows that had notable week-over-week rankings increases included Law & Order (0.48%, up from No. 30 to No. 17) and SpongeBob SquarePants (0.44% of minutes watched, at No. 19 from No. 26 previously).

Most-watched shows on TV by percent share duration for March 29 - April 4.

On the network ranking, CBS was in first place once again, but saw a week-over-week decrease in the percent of minutes watched, down to 7.51% from 8.27%. NBC moved into second place (7.01%), followed by ABC (6.70%), Fox News (4.02%) and Fox (3.74%). Multiple networks moved up the ranking from the previous week including CNN, ESPN, ION, Investigation Discovery and Food Network, while HGTV, TBS, USA, TNT and Univision dropped positions from the week before.

Also Read: Just How Much of a Slam Dunk Has March Madness Been on Live TV?

Most-watched TV networks March 29 - April 4.

Top Shows and Networks by TV Ad Impressions

Via, the always-on TV ad measurement and attribution company. Rankings are by TV ad impressions, for new episodes only. 

College basketball continued its domination, racking up 3.7 billion TV ad impressions during the week. American Idol broke into the top five with 659.7 million impressions, beating MLB games, which generated 589 million impressions. The Price Is Right and The Young and the Restless were the only other non-sports or news programs to make the top 10. NBA basketball, which was in fifth place for impressions the previous week, dropped to No. 10 (470.5 million impressions); PGA Tour golf also slipped down the ranking, from No. 2 to No. 14 (427.5 million impressions).

Top shows by TV ad impressions for March 29 - April 4

The top of the network ranking was stable week-over-week, led by CBS (8.1 billion TV ad impressions), ABC (5.4 billion) and NBC (4.7 billion). March Madness games accounted for over 34% of the impressions on CBS, while morning news shows were top drivers of impressions for both ABC and NBC (GMA and Today, respectively). MLB Network gained steam from the previous week, rising up to No. 12 with 559.8 million impressions. On the flip side, Golf dropped from No. 12 to No. 17, generating 377.8 million impressions during the period measured. Headline News was a ranking newcomer, with 58% of its 362.2 million impressions coming from The Death of George Floyd: Derek Chauvin on Trial.

Top networks by ad impressions March 29 - April 4