Women's clothing sizes convey vanity, insanity

Here are some numbers that illustrate the insanity of women's clothing sizes: A size 8 dress today is nearly the equivalent of a size 16 dress in 1958. And a size 8 dress of 1958 doesn't even have a modern-day equivalent - the waist and bust measurements of a Mad Men-era 8 are smaller than today's size 00.

These measurements come from official sizing standards once maintained by the National Bureau of Standards (now the National Institute of Standards and Technology), and taken over in recent years by the American Society of Testing and Materials. Data visualizer Max Galka recently unearthed them for a blog post on America's obesity epidemic.

Centers for Disease Control and Prevention data show the typical American woman today weighs about as much as the typical 1960s man. And though the weight story is fairly straightforward - Americans got heavier - the story behind the dress sizes is a little more complicated, as any woman who has ever shopped for clothes could probably tell you.

As Julia Felsenthal detailed for Slate, today's women's clothing sizes have their roots in a Depression-era government project to define the "average American woman" by sending a pair of statisticians to survey and measure nearly 15,000 women. They "hoped to determine whether any proportional relationships existed among measurements that could be broadly applied to create a simple, standardized system of sizing," Felsenthal writes.

Sadly, they failed. Not surprising, women's bodies defied standardization. The project did yield one lasting contribution to women's clothing: The statisticians were the first to propose the notion of arbitrary numerical sizes that weren't based on any specific measurement - similar to shoe sizes.

The government didn't return to the project until the late 1950s, when the National Bureau of Standards published "Body Measurements for the Sizing of Women's Patterns and Apparel" in 1958. The standard was based on the 15,000 women interviewed previously, with the addition of a group of women who had been in the Army during World War II. The document's purpose? "To provide the consumer with a means of identifying her body type and size from the wide range of body types covered, and enable her to be fitted properly by the same size regardless of price, type of apparel, or manufacturer of the garment."

The standard included the first modern women's clothing size charts, and it provides the first datapoints. Women's sizes ranged from 8 to 42. A size 8 woman had a bust of 31 inches, a 23.5-inch waist, and a weight of 98 pounds.

The government updated these standards again in 1970. But manufacturers were getting restless, Felsenthal writes. It became apparent the "representative" women measured for the standard weren't representative at all. Nonwhite women were excluded. The group of women from the Army were almost certainly fitter than the typical American woman. By 1983, the government had ditched the standard completely. Manufacturers were left to define sizes as they saw fit.

Enter the era of vanity sizing. Clothing manufacturers realized they could flatter consumers by revising sizes downward. The measurements that added up to a size 12 in 1958 were redefined to a size 6 by 2011. And different manufacturers defined sizes differently, too.

The American Society of Testing and Materials, a nongovernmental international standards organization, began trying to restandardize women's sizes in the 1990s. But by then, the sizing genie was well out of the bottle. If you've dealt with the frustration of buying or trying on women's clothes recently - particularly if you're short, tall, or in any way idiosyncratically shaped - you know most manufacturers ignore these standards.