Are 60-Sec ads twice as effective as 30-Sec Ads?
Andrew GreenZenithOptimedia
There has been a clear trend over the past 40 years to running shorter-length TV commercials.
In 1965, 77% of all US network TV commercials lasted 60 seconds, a share which dropped to 27% five years later and has since fallen to 7% (2004).
30-sec ads made up 23% of the total in 1965 and 72% in 1970, but fell back to 56% in 2004. 15-sec units, introduced in the late 1980s, made up a third of all messages by this date.
In the UK, similar trends towards...