Jan. 22, 2018
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There's a reason a size 10 at Zara is nothing like a size 10 at Macy's — the history of women's clothing sizes is pretty arbitrary.
Size charts weren't even a thing until the 1940s. Prior to that, sizes were based on age, which made individual adjustments necessary.
In 1939, the U.S. Department of Agriculture wanted to standardize sizes to save money on employee alterations, claiming it cost $10 million a year.
A heavily flawed survey of 15,000 women determined the first size standards. The survey was skewed toward lower-income white women, instead of a diverse sample.
The National Bureau of Standards took another shot and introduced another flawed standard in 1958, which heavily relied on a sample of fit Air Force members.
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Since 1995, ASTM International has published a table of measurements based on that 1958 standard. The problem is, the sizes don't really mean anything.
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That's because modern sizes are really based on vanity. Manufacturers frequently ditch official guidelines and re-label bigger sizes to appeal to psychology.
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You’ve probably heard that Marilyn Monroe was a size 12. But Marilyn Monroe was a 12 in the '60s; she'd be a modern size six.
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So, your size is arbitrary. Don’t spend too much time thinking about it, because the size you are now could be labeled differently in a decade.