Appreciation Index

The Audience Appreciation Index (AI) is a score out of 100 which is used as an indicator of the public's appreciation for a television or radio programme, or broadcast service, in the United Kingdom. Until 2002, the AI of a programme was calculated by BARB, the organisation that compiles television ratings for the major broadcasters and advertisers in the UK. Currently the AI is produced as part of an online Television Appreciation Survey, on behalf of the BBC Audience Research Unit, by GfK NOP.

As the individual ratings that produce the AI of a programme are recorded online the day after broadcast, the resulting score is usually available just two days after broadcast, though these scores are not generally made public by the BBC. The AI is considered especially useful for assessing the level of appreciation by viewers for programmes made for small or specialist audiences. If a television programme has performed only passably in the ratings, yet achieves a high AI, it can help to determine whether the programme should be recommissioned.

On average, programmes aired on the BBC's four main television channels (BBC One, BBC Two, BBC Three and BBC Four) for the period April–June 2013 received an AI rating of 82.3 and radio programmes received an AI rating of 79.9. The average AI for a drama programme on UK television channels BBC One and ITV1 was reported, in 2009, to be 84. Programmes with specialist appeal will often score higher ratings. Internal guidance to BBC production staff is that an AI of 85 or over is to be considered excellent, over 90 is exceptional, 60 or less is poor, and less than 55 is very poor. Sometimes a programme will not garner an AI, as the response for that programme may have been too small. Nor is the AI a conclusive measure; while it is valuable for comparisons within a particular programme category, comparisons between the AIs of different programme types (e.g. dramas with quiz shows) carry no weight.

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. The highest recorded score until the end of 2009 has been 97 for a US import on Sky1. Scores lower than 30 are very rare, though some party political broadcasts have received AI scores in the 20s. One criticism of the more general value of AI scores is that audiences tend to watch those shows they like, or expect to like, and so will tend to score them well.

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