MSNBC 9 PM host Rachel Maddow appeared on “Late Night with Jimmy Fallon” last night, and during her appearance let slip a fact that is well known in the TV news business, but does not often get talked about: when an anchor leaves the studio to go cover an important story on-site, the ratings usually go down.

“It is sort of an acknowledged truth in the news business that whenever you leave the studio, your ratings go down. No matter where you’re going, even if you’re going to cover somewhere exciting, your ratings go down.”

Whatever it is Katie Couric or Maddow going to Afghanistan, or Anderson Cooper on-site in Louisiana during the oil spill, viewers do not seem to respond.

Why do you think that is? Are viewers not interested in important, but depressing stories? Or does the studio format just make for a more entertaining show?

(h/t Mediaite)