When you buy vintage clothing there's usually a chart which comes close to this one, taken from the 1955 Sears catalouge. It's just a guide, you still have to check the actual measurements but any deviation is usually smallish:
Size 10: 32.5 bust, 24.5 waist, 34 hips
Size 12: 34 bust, 25.5 waist, 36 hips
Size 14: 35.5 bust, 27 waist, 38 hips
Size 16: 37 bust, 28.5 waist, 40 hips
Size 18: 39 bust, 30.5 waist, 42 hips
Size 20: 41 bust, 32.5 waist, 44 hips
Of course very few people wear corsets or control underwear on a daily basis any more and we have become taller too. Still, compared to say, a modern Zara (famously complained about for their small clothing) size chart:
xxs xs s m l xl
Chest (inches) 31.5 32.3 33.9 35.4 37.8 40.15
Waist (inches) 22.8 24.4 26 27.5 30 32.3
Hips (inches) 33.8 35.4 37 38.6 41 43.3
The XL comes out as between an old 18 and an old 20 and the XS more or less in line with an old 10. IME, on here, most people say Zara's XL is to be taken to mean a 12 - 14.