Doctor Who: The Woman Who Lived - Appreciation Index Score
Saturday's episode, The Woman Who Lived, had an Appreciation Index (AI) of 81.
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.
This is the lowest AI score so far for Series 9. Sunday's overnight viewing figures show that Doctor Who was the 37th most watched programme of the week.