(CNN) There were a lot of questions surrounding Netflix's eye-popping claim that more than 45 million accounts watched "Bird Box" over the holidays. There's now data from Nielsen that backs up that number.

Nearly 26 million viewers watched the film, which stars Sandra Bullock and Trevante Rhodes, over the first seven days of its release, according to measurement company Nielsen. This number does not include viewers outside of the U.S. and it doesn't include viewing that happened exclusively on mobile, tablet or laptops, which could explain why Netflix's number was so much higher.

Nielsen measures Netflix and other streaming data in the same way it measures television broadcasts -- by sampling the viewership habits of its panel of 48,000 homes and over 118,000 people.

The debut week viewership of " Bird Box " came in second to the debut week of season 2 of "Stranger Things" in October 2017, according to Nielsen, which has been tracking viewership on streaming platforms for about a year now. Netflix declined to comment on Nielsen's numbers.

"Bird Box" also stayed consistent after it premiered. It drew an average of nearly 4 million viewers a day in the U.S. in its first ten days.