The history of television ratings is of great interest to me because—to quote Maya Angelou—”if you don’t know where you’ve come from, you don’t know where you’re going.”

Market research firm The Nielsen Company, founded in 1923, is perhaps best known for its ubiquitous television ratings, but Nielsen actually started out measuring radio ratings before moving to TV in 1950.

Audience shares were initially calculated using paper diaries where customers wrote down the shows they watched and when.

Nielsen then used these diaries to compile statistical models that approximated viewing numbers.

Of course, as technology evolved so too did audience measurements, and just as paper maps gave way to GPS, Nielsen’s strategies similarly developed.

The company now forecasts ratings using a variety of television meters and set-top-boxes that remotely monitor TVs to see what shows and ads people are watching and for how long.

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