Netflix has revealed that the third season of its cult sci-fi show is its most popular to date, detailing the viewing figures in a letter sent out to shareholders yesterday. 64 million “households” tuned in to Stranger Things season three in its opening month on the streaming platform, earning it the title of the show’s “most watched to date”. 

Netflix did not reveal how it calculated those figures, but The Verge reported that the platform registers a person’s account as having viewed a series “if they substantially complete at least one episode (70 percent)”. To be clear, that’s 70 per cent of one episode, not 70 per cent of the series, which is… an interesting metric.

Back in July when the series was first released, a US data analytics company called Nielsen took its own measurement, finding that 26.4 million people in the US watched the show within its first three days. Netflix claimed over 40 million had watched it in the first four days worldwide. 

Whichever way you square it, Stranger Things has proved an enormous hit. A fourth series was announced in September with some fans claiming that Millie Bobby Brown’s character Eleven could appear as the villain.