Currently the AI is produced as part of an online Television Appreciation Survey, on behalf of the BBC Audience Research Unit, by GfK NOP.
[3] The AI is considered especially useful for assessing the level of appreciation by viewers for programmes made for small or specialist audiences.
AI scores in the 90s are less common, though this is less the case for niche, targeted programming that attracts a limited number of viewers, such US imports on smaller channels (such as Sky1), or for specialist programmes, or some very popular dramas.
[9] A flaw in the method became apparent when programmes with low audience numbers were left with a small, yet loyal, core of fans.
When commercial television launched in Britain in 1955, advertisers were less concerned about attitudes to programmes than they were about viewing figures, and this marked the start of the frequent measurement of audience totals.
The main Pulse measure, the AI or Appreciation Index, is obtained by respondents being asked to mark out of 10 each of the programmes they watched or listened to the previous day, where 10 is the highest score and 1 the lowest.
[11] Panelists are encouraged, by means of a prize draw reward scheme, to log in at least ten times in any one month.
[citation needed] At this time only a limited number of TV channels are covered by this rating system, and only broadcasts watched live, or in recorded form the same day, are given AI scores.
More extensive surveys, covering more channels and including programmes recorded for viewing within a week of broadcast, are occasionally carried out by smaller panels.
Other factors such as the amount of effort people take to view the programme or whether viewers found it entertaining were also important.