The Appreciation Index or AI is a measure of how much the audience enjoyed the programme. The score, out of a hundred, is compiled by a specially selected panel of around 5,000 people who go online and rate and comment on programmes.
The AI score is a slight increase from last week's series opener, Deep Breath. The only episode from the main two channels to score higher was Casualty, with an AI score of 85.
The Sunday repeat of Into the Dalek on BBC Three had an overnight estimate of 0.35 million viewers, gaining it a 1.85% share of the audience.