Chico's Pants and Jacket Set Denim Fish Abstract Pattern Art Outfit Small/Medium

I bought this in a excellent, perhaps unworn, condition last year. The pants are too tight in the butt for my liking, or I'd keep this fantastic outfit. Measurements and fabric content included in photos I don't understand chico's sizing. The jacket is a 1 and the pants are a 0. I would call the jacket a medium and the pants a 4. Both provide stretch I am 5'3 27/28 inch waist, 38 inch hips, 34D chest