Dayparting

In broadcast programming, dayparting is the practice of dividing the broadcast day into several parts, in which a different type of radio or television program apropos for that time period is aired. Television programs are most often geared toward a particular demographic, and what the target audience typically engages in at that time.

Nielsen Audio (formerly known as Arbitron until it merged with A.C. Nielsen Co. in 2013), the leading audience measurement ratings service in the United States, divides a weekday into five dayparts: morning drive time (6:00–10:00 a.m.), midday (10:00 a.m.–3:00 p.m.), afternoon drive (3:00–7:00 p.m.), evenings (7:00 p.m.–midnight) and overnight (midnight–6:00 a.m.).

In radio broadcasting through most of the 1990s, dayparting was also used for censorship purposes. Many songs that were deemed unsuitable for young listeners were played only during the late evening or overnight hours, when children were presumably asleep. Even today, the Federal Communications Commission (FCC) dictates less stringent decency requirements for programming aired between the hours of 10:00 p.m. and 6:00 a.m. local time.

The drive time dayparts coincide with rush hour; these dayparts are traditionally the most listened-to portions of the schedule, since these are the times when most people are in their cars, where radios remain nearly ubiquitous. Most stations (both talk and music) air local programming in one or both drive time slots. The midday, or "at work" slot, has in recent years become particularly prone to voice tracking, as large station ownership groups cut costs and use supposedly local jocks at multiple stations (often in different time zones). Music stations often are careful not to repeat songs during the midday shift, as they generally have a captive audience, and will often use "9 to 5 No Repeat Workdays" and all-request or specialty lunch hours to lure listeners and air a broader variety of music. Evenings are a popular time for syndicated programs, while overnights are generally automated, either with or without a voice-tracked jock, though there are a few niche programs that target special audiences in the overnight and early morning hours (Coast to Coast AM, Midnight Trucking Radio Network and the National Farm Report, among them). On weekends, music stations often air syndicated programming, without regard to time slots (though Saturday nights often remain live with either local or syndicated hosts, especially on oldies and country music stations, to take requests) and talk stations air niche network shows or brokered programming. Religious programming often airs on Sunday mornings.

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