One of the more frustrating things about streaming services is that they keep their viewership data to themselves. We can assume something like Stranger Things is a hit because people can’t stop talking about it online, Netflix gave it an aftershow, and it generates “buzz.” On the other hand, we can assume Girlboss was a failure because it was canceled after one season. However, there aren’t any hard numbers available to confirm those assumptions.

But finally, Nielsen—the company that’s been measuring television ratings since the 1950s—is trying to change that. In October, it announced a new “Nielsen Subscription Video On Demand (SVOD) Content Ratings” service. Then on Thursday, we got our first taste of the service in action when the company unveiled the apparent ratings for the second season of Stranger Things. As it turns out, our assumptions were right: Many people watch this television show. Per Nielsen, 15.8 million people tuned into the first episode of the new season by Sunday—more than cable powerhouse The Walking Dead, but still behind the most popular show on TV right now, which is, improbably, The Good Doctor. In total, each of the nine episodes of Stranger Things Season 2 drew at least 4 million viewers in the first three days of release.

There are, however, some caveats to these findings. Nielsen’s data don’t count Netflix users who are watching shows on their laptops or smartphones, and the company can’t account for subscribers outside of the U.S. (Other attempts to gather Netflix’s ratings have posited that Narcos is globally its most popular original series. Chief content officer Ted Sarandos has previously boasted Narcos is more popular than Game of Thrones, which is quite a flex.) That means that the data released on Stranger Things are just a modest estimate of how many people actually watch the show; the real number is assuredly much higher than 15.8 million.

So what’s the major takeaway here? Well, let’s just say there’s a good chance Season 2 of Stranger Things is bigger than The Good Doctor.