Yes - short answer.
In the early 1980โs I was size 14, and I sewed - a lot, and also worked in a very popular ladies boutique. The patterns I used were Simplicity and Vogue, and the sizing on those patterns matched what was on sale in the boutique (I checked, because people used to argue about sizes back then, too, so measuring the clothes when they came into the shop would give you ideas about which styles would fit people who didnโt fit into the clothes in โtheirโ size)
- UK Size 14 in 1984
- Bust: 36 inches
- Waist: 28 inches
- Hips: 38 inches (these were the max sizes)
- UK Size 12 in 1984 - all measurements were 2โ smaller
- Bust: 34 inches
- Waist: 26 inches
- Hips: 36 inches (again, max sizes)
- UK Size 12 now
- Bust: ~36-38 inches
- Waist: ~29-31 inches
- Hips: ~40-42 inches (varies)
โฆso not only have the measurements increased, but so has the proportion between them, with waist and hips measurement being fuller in proportion to bust measurement.
Based on these changes, the largest named measurements of size 12 now, is a 1984 size 16 bust, with a size 17 (i.e. in-between size) waist and hip.
As I recall, one brand of jeans back then (I think Falmers) used to send us their jeans in sizes 8, 9, 10, 11, 12, 13 & 14. We didnโt stock anything larger than a 14๐ฑ. They were the jeans that had white piping down the seams!