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← A Century of Fast · Lesson 2 of 3

Lines and curves

About it

Draw a straight line through the 27 points and it falls about 0.15 of a second a year. It fits well — r² about 0.95.

A curve that drops and then levels off fits a little better, r² about 0.97, and levels near 37.4 seconds. Where it levels is the curve’s guess, not a fact: the data stop in 2024, and nobody knows where the floor is.

The figure

A line and a curve through a century of winners

19081960202440 s50 s60 swhere the curve levels: a guessthe linethe curve
The Olympic men's 100 metres freestyle winning times from 1908 to 2024 as dots. A straight line through them falls about 0.15 of a second a year (r² about 0.95). A curve that drops and levels off fits a little better (r² about 0.97); the dashed line marks where it levels, which is the curve's guess, not a fact.
One question

The line falls about 0.15 of a second a year. Over the 16 years from 2008 to 2024, how much does the line say the winning time falls?

Say it back
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