"Twice Upon A Time" had an Appreciation Index score of 81 - close to the previous Christmas Specials "The Return of Doctor Mysterio", "The Husbands of River Song" and "Last Christmas" which all had a score of 82.
The Audience Appreciation Index (AI) is a score out of 100 which is used as an indicator of the public’s appreciation for a show. Over 90 is considered exceptional, 85 or over is excellent, 60 or less is poor, and less than 55 is very poor.
The AI scores for Series 10 are below:
The Pilot - 83
Smile - 83
Thin Ice - 84
Knock Knock - 83
Oxygen - 83
Extremis - 82
The Pyramid at the End of the World - 82
The Lie of the Land - 82
Empress of Mars - 83
The Eaters of Light - 81
World Enough and Time - 85
The Doctor Falls - 83
Smile - 83
Thin Ice - 84
Knock Knock - 83
Oxygen - 83
Extremis - 82
The Pyramid at the End of the World - 82
The Lie of the Land - 82
Empress of Mars - 83
The Eaters of Light - 81
World Enough and Time - 85
The Doctor Falls - 83
