NEW YORK: Average ad loads on national television have been creeping upwards, new research has said, averaging 10.9 minutes per hour during December.

Brian Wieser, senior analyst at Pivotal Research, analysed Nielsen data to arrive at the figure, reported in Broadcasting & Cable. That compared to 10.7 minutes in December 2015 and 10.4 minutes in December 2014.

Ad loads on Viacom networks were significantly higher, however, at 14.8 minutes an hour. NBCUniversal was also above average on 11.3 minutes, while Disney came in under on 8.1 minutes. All three had seen ad loads increase year on year.

Two networks reported a decline in the amount of advertising time per hour. Scripps Network Interactive was above average but had reduced its ad load from 13.4 minutes to 13.1. Time Warner was towards the other end of the scale, cutting back from 8.6 minutes to 8.5.

Earlier in January, Todd Juenger, an analyst at Sanford C. Bernstein, noted that shows on some networks had so many ads they no longer fitted the usual 30- or 60-minute programming slots.

He pointed in particular to cable networks belonging to Viacom, AMC Networks and Discovery Communications and suggested that the first of these was simply putting more commercials into its programming in order to offset falling ratings.

Viacom also had the biggest share of C3 ratings – live viewing plus three days of time-shifted viewing – among the crucial 18-49 year old demographic, at 15.4%, Pivotal said. It was followed by NBCUniversal on 14.7% and Disney on 11.8%. AMC saw the biggest gain in share, while Time Warner registered the largest decline.

Individual cable news networks mostly continued to see higher commercial audience shares in December following the November election, MediaPost reported.

Fox News Channel, favoured by the president-elect, saw its C3 rise to 1.4% from 1.3%, while that of CNN, dismissed by the president-elect as "fake news", dipped from 0.9% to 0.8%. MSNBC was up from 0.5% to 0.6%.

Data sourced from Broadcasting & Cable, MediaPosst; additional content by Warc staff