These were the 10 biggest TV shows in primetime this year

CBS had the most popular shows of the year.

Nielsen released its top TV ratings for 2015, and CBS dominated the primetime schedule with six of the top 10 programs.

"The Big Bang Theory" was second in viewership, and both "NCIS" and its spin-off "NCIS: New Orleans" landed in the top 10.

But the program with the most average viewers for the year was NBC's "Sunday Night Football."

Other sports-centered programs to crack the top 10 included CBS' "Thursday Night Football" and NBC's "Sunday Night NFL Pre-Kick."

These aren't big surprises: CBS has had the biggest overall audience for several years now, and sports regularly dominates ratings.

See the top 10 primetime programs of the year: