The rise of digital video is supposed to threaten the very economics of TV, drawing fans of “This Is Us” and “The Big Bang Theory” away from the big screen in the living room to the smaller pane on their smartphone. So how come Madison Avenue keeps throwing money at traditional couch potatoes?

The nation’s five English-language broadcast networks prevailed against disruptive trends brought on by new streaming-video technology and managed to snare a gain of between 3% and 5% the volume of advance advertising commitments they secured for their next cycle of primetime programming, according to Variety estimates, part of the annual haggling of TV’s “upfront” ad-sales marketplace. The networks secured between $9.1 billion and $10.06 billion, according to Variety estimates, compared with $8.69 billion and $9.55 billion in last year’s haggle. It is the third consecutive year that the networks have seen increasing volume for their primetime schedules. Many of the big cable programmers are also done, with one or two still in the midst of selling.

And while the numbers are little more than fuzzy math, they suggest the big TV networks may have surpassed, finally, the record set in 2004 when six broadcast networks – the WB and UPN were still around, in place of CW – secured around $9.5 billion. One of the big drivers behind the results is the launch of an extra night of programming at the CW, a move that increases that network’s national ad inventory by 20%.

TV executives know they are losing viewers to streaming services like Netflix, Amazon and Hulu, and they realize their linear ratings – the measure upon which most of their ad deals are based – are in significant decline. But Madison Avenue isn’t punishing them for it – at least not yet. “Supply is not what we want it to be, and we have to face that,” says Jon Steinlauf, the chief advertising sales officer at Discovery Inc., in an interview. “But demand held.”

It may not do so for long. U.S. digital ad sales, fueled by rocketing interest in mobile video, are expected to rise 15% in 2018, according to Magna, a media-research unit of Interpublic Group., to $106 billion. The forecaster sees national TV ad sales rising just 0.2% to $43.4 billion. Many of the stalwarts of TV advertising – automotive marketers and retailers – are in the midst of severe disruption. At some point in the not too distant future, companies like Ford and General Motors may make more cars for ride-share services than they for individual drivers. Many big store chains are being winnowed down by Amazon. And there is a growing phalanx of upstart brands – Blue Apron, Dollar Shave Club, Axios and more – whose recognition has been stoked by large doses of digital and social communication, rather than entirely by TV ads.

These advertisers often need to run longer commercials to explain side effects of their various medications and they realize they can run those commercials more cheaply in daytime and late night, where commercial prices are cheaper. But that demand can take up inventory others might want and help networks sell packages of ads that also include primetime.

And for all the ballyhoo accorded digital giants like Facebook and YouTube, advertisers have found a lot to dislike about those outlets. They are frustrated by efforts to measure the effectiveness of the ads that run on those platforms. More important, they remain concerned about so-called “brand safety” issues that could result in an ad for shampoo or soup turning up next to an unsavory or offensive piece of content. Unilever, one of the world’s biggest advertisers, has in recent months demanded higher-quality digital environment and more transparent accounts of social-media activity.

They can get some of that from the TV companies, which just happen to stream and post video themselves. Digiital ad commitments at Disney/ABC Television and NBCUniversal each rose 25%, according to people familiar with results.

While many more people are watching their favorite “Grey’s Anatomy” episode on Netlfix or Hulu, TV continues to bring in the largest number of people all tuning in at the same time for a fresh “Walking Dead” episode, a Sean Hannity or Rachel Maddow segment or a big football game. “The vast majority of television viewing is not streaming. The vast majority of television viewing is not Netflix or Amazon or Hulu,” aid NBCUniversal CEO Steve Burke during a conference call with investors Thursday. “The vast majority of television viewing continues to be linear television for big events.”

Viewership declines in some ways helped TV networks. The dip in supply means advertisers have to pay higher rates and run ads more times to generate the same amount of reach among consumers. Volume and pricing gains were the order of the day across the board at the networks – and in many cases were more robust than they were in 2017

NBC was able to secure a 7% increase in primetime volume, according to a person familiar with the matter,which could mean $2.92 billion in advance ad commitments. Primetime volume in 2017 is believed to have increased between 8% and 9%, to $2.73 billion. NBC pressed for increases in the rate of reaching 1,000 viewers, a measure known as a CPM that is central to these annual discussions. NBC sought hikes of more than 11%, according to Burke. In last year’s sessions, NBC pushed for CPM hikes of between 8% and 9%.

CBS may have seen an increase of 1% or more in primetime volume, according to people familiar with negotiations. If that’s the case, then CBS might have secured between $$2.28 billion and $2.63 billion for its primetime schedule, compared with $2.26 billion and $2.6 billion last year, when volume was flat with 2016. CBS pressed for CPM increases of between 9% and 10%, on par with the rates it sought in the 2017 session.

ABC saw an increase in primetime volume of between 6% and 8%, meaning the Walt Disney owned network could have secured between $1.86 billion and $2.2 billion. In 2017, the volume of advance ad commitments for ABC’s primetime schedule rose 3% to 5%. ABC sought CPM hikes of between 10% and 11% this year, compared with rate increases of between 8% and 9% last year.

Fox’s primetime volume may have increased 1%, the result of advertisers’ interest in the network’s new lineup of “Thursday Night Football” games. The volume of advance ad commitments for Fox’s primetime schedule – typically just 15 hours a week – could come to between $1.48 billion and $1.66 million, according to Variety estimates. In 2016, Fox secured volume of about $1.47 billion to $1.64 billion. Fox sought CPM increases of between 9% and 10% for its primetime schedule, compared with between 6% and 8% in 2017.

The CW’s volume grew the most, owing primarily to the extra night of programming. Volume of advance ad commitments rose 15% to between $564.5 million and $631.8 million, compared with 2017, when volume rose between 3% and 5% to between $490.9 million and $549,4 million.

The numbers aren’t handed out via press release or filed – except in rare circumstances – with the Securities and Exchange Commission. They can mean whatever network sales executives and media buyers want them to mean. Some people make the specious assumption that upfront figures are automatically deposited in the coffers of media conglomerates like 21st Century Fox, Time Warner CBS Corp., Comcast Corp., Viacom and Walt Disney Co.

That’s not the case. In the upfront, advertisers agree to spend a certain amount of money in the coming season. But they can cancel a portion of their upfront commitments each quarter, and can even pull their money if a show they agreed to support is canceled and the two sides can’t come up with a different schedule of commercials.

In the end, the upfront totals are merely directional indicators, essentially telling us how much Madison Avenue values TV at a particular moment in time. In 2018, it’s clear advertisers won’t abandon TV. But if TV viewers keep toggling their screens to streaming and on-demand services, advertisers will eventually have to follow.