"Ad loads (i.e. commercial minutes per hour of programming) have been increasing steadily across the industry since 4Q17 (the same time ratings began to deteriorate)," UBS TV industry analyst John Hodulik points out in a thorough analysis of network supply-and-demand, including their ad inventory.
"Year-to-date, cable network ad loads have been up 3% on average across all networks tracked by Nielsen," he found.
With the exception of NBCU's cable networks, all of the major cable groups are at or near their all-time clutter highs.
The picture is not much different for the major broadcast networks. With the exception of some reductions earlier this year at Fox, the broadcast marketplace has been boosting
the supply of commercial minutes to offset audience erosion.