CBS is excited about the viewer turnout for the premiere week of “The Late Show with Stephen Colbert.” The network says the show was the most-watched program in late-night, delivering an average audience of 4.45 million across its four-day premiere week.

That’s an increase of 95% from the same week a year ago (2.28 million), the network said, citing Nielsen live plus same day figures.

Key demos were all up significantly for the four days ending Sept. 11: up 125% in adults 18-49 (0.9 average rating, up from 0.4); up 250% in adults 18-34 (0.7 average, up from 0.2); and up 100% in adults 25-54 (1.2 average, up from 0.6).

“Digitally, the premiere episode of ‘The Late Show with Stephen Colbert’ marked the best series debut ever for any CBS show in terms of full episode streams on CBS.com and the CBS apps — even topping all CBS primetime shows — and broke ‘The Late Show’s’ previous traffic records on both platforms,” CBS noted.

“The Late Show” was also the most social late-night network talk show of the week, according to Nielsen Social.