Sundresses and Vanity Sizing/Size Inflation

Last Spring I thrifted a bunch of new (to me) sundresses, but they didn't see the light of day since we had such a horrid and cold summer in British Columbia.  But, when we went to Mexico in February, I finally got to wear them.  Hopefully, I'll get more chances this summer.  Two are vintage (late 1980s) and the other one is newer - but all are made in Canada.
First the vintage ones...

 I got this one at a clothing swap fundraiser for a donation of $2.  Made by Les Mode Jolibel Inc, is is 100% cotton.  Notice how snug and well-fitting it is?  Size 10.  It is totally something I would have worn back in the day.  When my mom (who was in Mexico with us) saw it, she said I looked like I did back in the 1980s.  I take that as a complement!

 This one was purchased at Value Village in Coquitlam, BC for about $17. I love the pattern.  Although it feels like linen, it is also 100% cotton made by Seaqueen beachwear and swimwear.  I have a little shrug that dresses it up nicely.  It is also a size 10.  I also love that both of these vintage dresses have pockets.  So handy!

And finally the new one....

 This is Joseph Ribkoff, a Canadian design house that has been around since 1957.  Purchased at Value Village in Prince George, BC for about $15.  No pockets, and a synthetic material.  It also fits my torso well, but as compared to the size 10 1980s dresses, this one is a size 4!  Obviously, there is some discrepancy here.

And it is not just this dress. I have recently purchased a pair of jeans in a size 4, a few skirts, and many tops.  There is some controversy whether this trend is 'vanity sizing' (manufacturers purposely putting smaller sizes on clothing so vain consumers purchase the clothing) or 'size inflation' (manufacturers changing their sizing to reflect today's 'average' which is heavier and taller than it used to be).  Of course, studies show that even men's trousers (ostensibly measured in inches) do not reflect an accurate measurement.  A size "31" may actually measure as a "35."

All I know is that I never wore a size 4 when I reached adulthood and started shopping for myself.  Twenty years later, even with changing sizes, I still can't think of myself as a size 4.  I prefer to think of myself as a perfect (size) 10! Ha Ha!