The American television measurement by Nielsen is based on three different methodological approaches. In the 25 TV markets with the highest sales (e., g. New York, Los Angeles, Chicago, Denver), the Local People Meter (LPM) is measured. Individuals register individually; the measurement is carried out on 365 days over 24 hours. The SET Meter (Diary & Electronic) is used in 31 smaller markets (such as Nashville, Salt Lake City). In four sweeps in February, May, July, and November, target group data are collected with the diary and validated with the data of the devices (TV set on/off) in the participating households. In the 154 TV markets with the lowest sales (e. g. Harrisburg, PA or Honolulu) the use of TV is only recorded using a diary survey.