This is why I don't use my clothes or a particular size as an indicator of success. I use the scale (yuck, I know) and my measurements. Granted this is for men's pants but I imagine the discrepancy in women's pants is even crazier. Imagine Old Navy is a full 5 inches bigger. 5 inches is a lot of extra poundage on the midsection.
I am happy to no longer be in the "women's" or "plus" section. I look forward to the day when even more options are open to me. I am on the border still between Plus and Regular sizing. With the large chest I still have to reach for XL or XXL to cover up the ladies. Otherwise I could give a crap about the size of the clothes I am wearing.