Podtrac’s ranker for the most listened-to podcasts during the month of April brought a familiar list of top shows – despite changes in the algorithm for how downloads are measured. The New York Times-produced morning news podcast The Daily remained the most listened-to show. This American Life and iHeartRadio’s Stuff You Should Know each moved up a spot as Daily Wire’s Ben Shapiro Show slid from No. 2 to No. 5. The ranker is based on U.S. monthly audience figures, although Podtrac doesn’t make public the actual listening data for each podcast.

Here’s the list of the top shows in April among publishers measured by Podtrac:

The numbers released for April reflect an update made by Podtrac to the measurement algorithm that calculates unique downloads. The company says it has made tweaks and adjustments to its algorithms during the past 14 years that it has been measuring podcasts, but the latest is “more significant” than in the past. It’s brought about by Podtrac’s embrace of standards develop by the Interactive Advertising Bureau (IAB) Tech Lab. The IAB’s Podcast Measurement Technical Guidelines 2.0 change what counts as a download. For example, in the past, if someone were to listen to a podcast, press stop, then play again, that would count as two downloads. Now, it counts as one. Plus, someone needs to listen for a full 60 seconds before it counts as a download. Podtrac says that most podcasters didn’t see a “substantial” change in their unique monthly audience numbers, however download numbers mostly declined because of the new guidelines.

The new IAB v. 2.0 standards were adopted in December 2017 and Podtrac says for the months that followed there wasn’t much interest from advertisers or publishers in the certification process. It notes there was a question whether member companies of the technical working group would pay for and undergo certification and, as a result, only five of the more than 40 member companies have completed the process. But in 2019, the tide may be shifting.

“Increasingly, advertisers are getting behind the IAB Compliance Program as a way to make it easier and more reliable for them to make advertising decisions across multiple shows, publishers, hosting and ad insertion companies,” Podtrac says in a blog post. “They now often request companies that submit advertising proposals to identify shows with IAB 2.0 certified counts.”

Podtrac expects to have a clearer picture of the impact at the podcast or publisher level in July, when the data for June listening is released. It is recommending clients hold off in making changes to their ad rates based on the numbers until then.