On Monday 59% of flights left T5 within 15 min and the average delay of 22 minutes.

On Tuesday 70% of flights left within 15 min (32% left exactly on time) and the average delay was 15 minutes which is a similar performance to last Wednesday when 71% of flights left T5 within 15 minutes. Both of these days were far better than T1 punctuality pre 27th March.

My question is, what do you consider to be an acceptable percentage given that BA are operating out of LHR.