I've noticed this too. I'm spending less on clothes because the clearance racks seem to have my new size. Although sometimes there are cruel twists of fate where it seems like I all see is my old size in a pair of jeans I want

It happened the other day when I wanted a pair of these skinny jeans I like in a smaller size. They had 0 and 12, that's it! I'm SO not a 0, and the 12 would be way too big on me at this point!
I bragged about this in another thread, but I spend $98 the other day at Old Navy because of a half off clearance sale and a 25% coupon. I got four pairs of jeans, a winter jacket, a pair of exercise pants and about 10 tops.
I looked in my old sizes, there was nothing there—not to that extent anyway. I've never been able to go to the clearance section and clean up like that. I instantly got a wardrobe when previously I was scraping by with the same five or six things that were a little too big on me (I've never been this small, so no closet shopping for me)
It's great for in-between clothes to get them cheap. I don't want to spend a lot on clothes I may not be able to wear for much longer.