The Next Doctor - Appreciation Index
Monday, 29 December 2008 - Reported by Marcus

The Appreciation Index, or AI, is a measure of how much the audience liked the programme. It is a score out of 100, based on responses from a carefully selected panel. The average score for drama on BBC1 and ITV1 is 77. A score in excess of 85 is regarded as excellent while a score below 60 is poor.
With overnight figures now available for the whole of Christmas week, Doctor Who stands as the second most watched programme of the week, a position it is expected to retain when BARB releases the corrected figures next week. If so this would be the fifth top five place in succession, a record for the programme.