system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How are the total number of viewers for a given TV show calculated?

**Let's use a sporting event as an example:**

The *FSU - Notre Dame* football game was estimated at 13.25 million viewers. There seems to be a lot of things that could be considered when estimating the number of people who watched the game:

* How many TVs tuned in

* The number of people watching each TV

* What about the dozens of people who go to the bar to watch a game on a few TVs?

* What about the people who leave their cable boxes on and only turn the TV off? If the cable box was on the same channel as the game, doesn't that count towards the number?

Can anyone break down how viewership is calculated?
gpt
Ratings take a small slice of people who report on their viewing habits and then they extrapolate that figure across the entire viewership.  If .05% of your viewers are reporting, you take those reports and multiply it by the actual number of supposed viewers to get an estimate.

I wouldn't be surprised though if that goes away in a few years.  Most cable TV companies or TV providers should have the ability to tell what channel each box is on.  It wouldn't take much to make such data available for ratings without identifying households.

It would, of course, cause an uproar, which is why although the capability likely exists, they don't do so.