Women’s clothing sizes have undergone tremendous changes through the years. What was a size 16 in 1958, is equal to a size 8 today, and a size 8 dress in 1958 does not even have an equivalent today. Official sizing standards once maintained by the National Bureau of Standards (now the National Institute of Standards and Technology) has cited these measurements in women’ s wear.
Today’s women's clothing sizes apparently 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, as per Julia Felsenthal who detailed over at Slate.
The National Bureau of Standards published ‘Body Measurements for the Sizing of Women's Patterns and Apparel’ in 1958. The purpose was to provide consumers a means to identify their 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. This is when the first women’s clothing size charts were included and it provided data points.
In 1970, again the government updated these standards, however, it was obvious that the ‘representative’ women measured for the standard weren't representatives of all. So, by 1983, the government ditched the standard completely and manufacturers had to define sizes as they saw fit.
After a few years, clothing manufacturers realised that they could flatter consumers by revising sizes downward. Also, different manufacturers defined sizes differently. A non-governmental international standards organization, The American Society of Testing and Materials, began trying to restandardise women's sizes in the 1990s. Yet, women find it frustrating to get the right size and navigate through the chaos of arbitrary sizing on their own.
