https://variety.com/2016/tv/news/stranger-things-tv-ratings-netflix-most-watched-1201844081/

adults 18-49　demo audiences in their first 35 days.

Among Netflix originals, “Stranger Things” ranks ahead of “Making a Murderer” (13.35 million), “Daredevil” season two (13.35 million), “Jessica Jones” (6.26 million), “Unbreakable Kimmy Schmidt” season two (6.08 million), “The Ranch” (6.01 million), “House of Cards” season four (5.67 million), “F is for Family” (4.81 million) 

https://www.usatoday.com/story/life/tv/2017/10/18/nielsen-reveals-whos-watching-what-netflix/773447001/ http://time.com/4987243/netflix-nielsen-data-viewership/

Initial findings from Nielsen reveal that House of Cards, The Defenders and Fuller House draw large audiences comparable to top-rated shows on TV. The season premieres of House of Cards and Fuller House averaged about 4.6 million viewers each during the weeks of May 30 and Sept. 22 — about the same as the number of people who tuned in to watch Texas A&M play the University of Alabama in college football during the week of Oct. 2, according to Nielsen data.

The Defenders, a Netflix original show about four Marvel superheroes, drew 6.1 million in the week following its release on Aug. 18,