The Antikythera mechanism had a whole set of gears specifically to track the cyclic popularity of skinny jeans and low-rise waists.

"Lunar Cycles", by Randall Munroe, licensed under Creative Commons Attribution-NonCommercial 2.5 License

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The Antikythera mechanism had a whole set of gears specifically to track the cyclic popularity of skinny jeans and low-rise waists.