Complex sentence: Overnight viewing figures estimate that the episode was watched by 4.7 million viewers, rising to 6.64 million after calculating the final ratings, making it the ninth most-watched programme of the week on BBC One.
Split into simpler sentences: Overnight viewing figures estimate that the episode was watched by 4.7 million viewers. When final ratings were calculated, the figure rose to 6.64 million, making it the ninth most-watched programme of the week on BBC One.