The New York-based president of Nielsen's media unit, Steve Hasker, said predictions of a TV bloodbath from digital video streaming had gotten out of hand. The effect on TV viewing habits, he said, was vastly overhyped, although partially understandable given the billions of online views that digital video platforms were racking up daily.

Mr Hasker said mobile and PC video streaming in the United States still only accounted for 1.5 per cent of the total minutes Americans spent watching broadcast TV every day. The confusion, he said, was because people were crudely comparing the gross number of "views" online with the actual amount of time people spent with broadcast content.

"We're seeing tremendous confusion as to what the reality is around digital video," Mr Hasker told The Australian Financial Review during a visit to Australia. "If you ask any media buyer on Madison Avenue what is going on in TV, they will say 'oh, digital video – it's growing fast, whereas TV ratings are coming down'."

However, Mr Hasker said while television ratings measure audience numbers, digital broadcasters talk about total views. "The television industry in the US has not really done enough to clear that up and we haven't done enough to help them clear that up," he said. "But we're very much mobilising around the idea of total audience metrics so that people, particularly marketers, can understand how big a digital video service actually is relative to TV."   

The proliferation of devices and viewing options has snagged TV broadcasters because traditional TV ratings only cover viewing on TV sets, despite broadcaster content increasingly being viewed on smartphones, tablets and computers. Nielsen was now moving to measure behaviour across all video channels and devices in the US.

Mr Hasker said US TV broadcasters had seen "headline ratings" decline 8 per cent to 15 per cent in the past two years, attributing much of that to subscription video on demand (SVOD) services, namely Netflix, rather online viewing of short- and long-form content. But understanding viewing trends was complicated because some TV networks like CBS and ESPN in the US had actually lifted their ratings in recent years and primetime and live sport ratings for TV "had held up well".

Mr Hasker said Netflix in the US, which has about 40 million subscribers, equating to 60 million to 80 million people, materially hit TV viewing midway through 2014. "In June or July last year, when the [TV network program] originals came off air and re-runs came on, American households faced the choice – do they watch reruns on broadcast or Netflix?"

In contrast to traditional broadcasting, Netflix gave viewers "complete control" and ad-free programming. "That's what drove the decline in ratings," he said.

But the TV ratings declines were "not all year round", Mr Hasker said. "It's not every day and it's not every genre. When you average it out, it is a decline in the amount of time spent watching TV [overall], but for leaders in the US market like CBS or ESPN, there are actually more people watching their stuff … If you go to some other networks who have not had such a great [programming] record, the fact is their audiences have drifted elsewhere."

Mr Hasker said the ad-free approach from SVOD services also meant advertisers would end up paying higher ad rates to TV broadcasters to reach audiences.

"The US consumer, like the Australians, will only spend so much, so there is a real role for ad-supported content," Mr Hasker said. "And as more and more content is viewed through SVOD, in a sense the eyeballs that are on ad-supported channels become more valuable. But the one risk that is out there is the industry broadly is training consumers to be less tolerant of advertising."

Mr Hasker said Nielsen was focused on "getting [audience] reach metrics across all video, no matter where it's seen, no matter who looks, so it's consistent and feeds into media buyers' models and decision-making so that they truly understand the comparability between media."