Television ratings should see a boost with Nielsen’s decision, announced this morning, to add viewers who stream shows via Hulu and YouTube TV to the mix.

The audience measurement firm says that it will include viewers watching linear broadcasts live, on DVRs, or on-demand platforms on  desktop computers, tablets and smartphones. They will go into the C3 and C7 results, which measure commercial viewing up to three and seven days after a show airs.

But the content, and the ad load, must match what people would see on traditional TV platforms.

The change “is a major accomplishment in delivering Nielsen Total Audience to the marketplace,” Nielsen Product Leadership President Megan Clarken says. It’s “part of our commitment to provide trusted, independent measurement of the evolving modern media landscape.”

Network execs have complained that Nielsen numbers that show TV audiences shrinking failed to capture people who watched their shows on digital platforms. The lower numbers depressed ad revenues.

Disney’s ESPN, one of Nielsen’s sharpest critics, applauded today’s news.

ESPN SVP of Marketing and Consumer Engagement Wanda Young calls it “an important step forward toward complete cross-platform measurement.”

YouTube TV, which has promoted its ability to offer all of the Big Four broadcast networks in major markets, also likes the change.

Live TV “represents the majority of time spent watching on the service,” says Director of Content Partnerships Heather Moosnick. “Our network and advertising partners will benefit from Nielsen [digital TV ratings] measurement of Y​o​uTube TV.”