Time spent listening (TSL) is one of the measurements surveyed by Nielsen Audio in determining ratings for radio stations in the United States. It is the equivalent of AverageTime Exposed (ATE), Daily or Weekly. TSL is defined as the amount of time the average listener surveyed spent listening to each radio station at one time, before changing the station or turning it off. Alternately, it is an estimate of how long the average panelist (listener) was exposed to a particular station or stations for a specific time period. * v * t * e * v * t * e