Netflix famously does not release its viewing figures - so this estimate from Luth Research is the closest thing we have to knowing who is watching its original series.
The data was drawn from a pool of 2,500 American Netflix subscribers viewing by computers, tablets or smartphones. Luth Research company looked at the number of subscribers who viewed original Netflix series in the first days of their release and then estimated the total audience from there based on the streaming service's 40.9 million US users.
As this chart from Statista shows, Luth Research found House of Cards' third season was not nearly as popular as Unbreakable Kimmy Schmidt or Daredevil.
Netflix refused to comment to Variety, who first reported the findings.