The launch episode of The The X Factor 2012 has scored the lowest viewing figures for a series opener since 2006, according to overnight estimates.

The figures reveal that the first show of the series – which introduced new judge Nicole Scherzinger as well as guest panellist Mel B – was watched by an average of 8.1m viewers – rising to a peak audience of 9.9m in the second half of the show.

By contrast, the 2011 series kicked off with an opening show audience of 10.8m while the 2010 series – the last to feature Simon Cowell, Dannii Minogue and Cheryl Cole – was even more popular, pulling in 12m.

However it was still the most watched show on Saturdy evening, with the BBC’s screening of Indiana Jones And the Kingdom of the Crystal Skull, and latest episode of Casualty unable to compete – although Indiana Jones did beat returning gameshow Red Or Black in the ratings, with 4.9m compared to the 4.1m who tuned in to see the first edition.

Saturday’s X Factor featured early front runners including supermarket worker Jahmene Douglas and songwriting teenager Ella Henderson, as well as the controversial backstage tantrum from Pink lookalike Zoe Alexander.

Viewing figures for the show have fallen over the past couple of years, with 13.1m tuning in to see Little Mix triumph in the 2011 final.

By contrast the 2010 final, which was won by Matt Cardle, was seen by an audience of 17.2m.