Number of the day: 15th season for 'Always Sunny' sets new US sitcom record

(L-R) Actors Kaitlin Olson, Danny De Vito, Rob McElhenney, Glenn Howerton and Charlie Day at a Paley Center event for 'It's Always Sunny In Philadelphia,' in California, USA, April 2016

Each day, ETX Studio puts the spotlight on a number that stands out for making headlines in one way or another. Now renewed for a 15th season, US show "It's Always Sunny in Philadelphia" has broken a record held for nearly 60 years by black-and-white comedy series "The Adventures of Ozzie and Harriet."

Don't expect to see it before 2021, but vice comedy "It's Always Sunny in Philadelphia" is returning for a 15th season.

In doing so, it becomes US TV's longest-running live-action situation comedy, a title previously held for nearly 55 years by "The Adventures of Ozzie and Harriet."

An impressive feat, but the designation is important.

Of course it excludes soap operas, chat shows and news bulletins, but it also rules out animation ("The Simpsons," 31 seasons plus), sketch shows ("Saturday Night Live," 45 seasons), and raw episode counts ("Ozzie and Harriet" had 435, "Always Sunny" has 154).

Focusing on US TV also excludes the international scene, such as Sri Lankan coffee shop dramedy "Kopi Kade" (over 1,700 weekly episodes since 1987) and Hindi apartment block sitcom "Taarak Mehta's Upside-Down Spectacles" (over 2,900 episodes since 2008).