Advertising income has been the lifeblood of commercial TV for decades, but declining linear audiences—combined with digital video alternatives—mean the TV advertising model must evolve to ensure it remains as potent a medium for brands as ever.

Lack of effective audience measurement and somewhat opaque advertiser/agency/sales house relationships are hampering linear TV advertising revenues. Both issues need resolving to underpin a healthier ecosystem overall.

Flexibility is key to this evolution. A move to audience buys across most linear and BVOD inventory would provide greater flexibility and targeting for advertisers, and would sit alongside some premium context buys. A greater onus on volume deals would give broadcasters more certainty to invest in content and their advertising propositions.

In this report, we examine the completion rates of every scripted series since 2018 across all the major UK broadcast channels.

Comparing scripted programmes across different channels by overall viewing is difficult as these numbers are affected by promotion, prominence, competition, the quality of online player UIs and availability.

The rate that series are completed—viewing of the final episode as a proportion of the first episode—eliminates these and allows comparison.

Linear TV's decline continued into 2018, with an overall drop of 3% across the first 12 weeks YOY. However, overall TV set usage remained flat at 4 hours/day, as time spent on unmatched activities—which includes Netflix, Amazon and YouTube—continues to rise.

Within the ever-shrinking pie of consolidated viewing to the TV set, share of viewing (SOV) to the ten largest channels remains broadly flat. Across the whole of 2017 and the start of 2018 the best performer has been ITV (main channel).

Several big-name digital channels are showing surprising signs of recent decline, including UKTV’s Drama and Viacom’s 5USA. It is too early to tell if these declines are a blip or a trend. However, they reflect stalling growth from the long tail of digital channels in aggregate.