As mentioned, it’s all about the hip/waist ratio. I’m tallish at 5’10–I’ve also been ill for a while and lost a bit of weight, but I think I’m 36, 24, 37 (curse of the bubble butt). I think genetics play a big part becuase even at my skinniest, my hips were still 36 inches.
I’ve notice a trend in Penthouse and Playboy though where the girls have smaller hips in proportion to their bust e.g., 36, 24, 32. They seem normal enough, but I’d have to wack off the crest of my hip bone to do that 
My parents’ 50th wedding anniversary is coming up in June, and when I was home last we were looking at their wedding album. Unfortunately, her wedding dress was destroyed in a fire, but she does still have a belt that my grandmother had made for her at the time. When my mother got married in 1954 (at the age of 20), she had a 19" waist and she was about 5’5" tall.
I have no idea what her bust measurement was (and stop looking at my mom’s rack, you pervert).
Where do you shop?
I also have a waist of 29-30 and hips at 41, but I don’t fit into anything smaller than a 10 (and a 10 is stretching it, usually. In the brand I buy jeans in, I’m a 13/14). An 8 is entirely out of the question, much less a 6 (or misses 7 - I do, however, outweigh you by quite a bit.)
I have heard that the average woman is 12 which (according to the Lands End catalog) means she’s got a 30 inch waist and 40 inch hips.
FWIW, that’s what I’ve heard as well. I can’t believe plnnr’s Mom had a 19" waist. Holy cow that’s tiny, as my Uncle would say, “I poop bigger than that!”
Well, today I am wearing some dress pants from Express and they are size 6. I wear a 7/8 in their jeans. The only time I wear anything above a 7 is when I try to shop in Junior sections of stores, then I wear a 9. I wear a dress size of 5/6 or 7/8. I would absolutely swim in a size 12.
I’m proportioned differently than a lot of women. My thighs are not big, but my butt is very round and sticks out. It isn’t wide so much as it’s round. I think that’s where the extra inches come from. And my waist is 29 inches, but I have no fat on my stomach, it’s very flat. Maybe someone who wears a bigger size has more belly under their waistline. I don’t know.
I’ve read or heard many times that in the Victorian era, women used corsets to squeeze themselves down to a 17" or 18" waist (wasn’t that about what Scarlett O’Hara’s was in GWTW?). But I always wonder what that measurement would be without the corset. I’ve also seen some photos of Victorian ladies that made them look plump enough to me, at least compared to today’s runway models. And how about pictures of women in the 50’s & 60’s in bathing suits - I’m saying there was a beauty standard that was much healthier than today’s (neither fat nor heroin-chic skinny).