The sweeps system, which originated in radio, has been around for almost fifty years, and it shows. Every February, May, July, and November, Nielsen sends out 2.5 million paper "diaries" to randomly selected people in almost every TV market in the country and asks them to record, for a week, what programs they watch. The networks' local stations — the affiliates — and local advertisers then use the information from those diaries to negotiate ad rates for the months ahead. Each year, sweeps determine how more than twenty billion dollars in ad money gets spent. ...

What's wrong with them? To begin with, they force the networks to rely on "stunt" programming — to pack their schedules with outrageous specials, celebrity appearances, and expensive movies. The more juicy stuff the networks pack into sweeps months, the less they can afford to put on during the rest of the year.
—James Surowiecki, "The Way We Watch," The New Yorker, February 17, 2003

Network viewing in cable homes has dropped from 49 percent a year ago. Media experts claim a major reason behind the fall is a decision by the Big Four (ABC, CBS, NBC, and Fox) to use fewer "stunt programs" to lure audiences during the November sweeps.
—Dusty Saunders, "Cable TV making connection," Rocky Mountain News (Denver, CO), December 23, 2002

Tonight, Fox premieres "Married . . . With Children" at 6 p.m. and "The Tracey Ullman Show" at 6:30. But, borrowing a programming strategy from cable operators, on its premiere night, Fox will show each comedy three times in one night, giving audiences opportunities to find it. More importantly, it makes it harder for the networks to create competitive "stunt" programming ploys to blunt Fox's debut.
—P. J. Bednarski, "Will quick new Fox jump over 3 top dogs?," Chicago Sun-Times, April 5, 1987