Downton Abbey drew its lowest audience for the launch of a series for four years when it returned to TV.

The first programme of the fifth series of the ITV show had an average of 8.4 million viewers – more than a million fewer than the 9.5 million who turned in for the start of last year’s series.

Only the very first Downton launch in 2010, which premiered with 7.6 million, had a lower audience. The programme was still easily ahead of the BBC One drama Our Girl, which had an average of 3.9 million viewers.

Most-watched programme of the night on Sunday was The X Factor, which drew 8.7 million – up 200,000 on the previous week’s figure.

But it was down by more than a million on the equivalent show of 2013, which had an average of 9.8 million viewers.