How many oz of formula is your baby taking?

My baby will be 9 months next week and loves solids. We’ve been doing mainly purées but introduced solid pieces with her developing pincer grasp. I’m worried she’s really dropping in her ounces of formula per day. Our doctor said to follow her lead and just make sure she’s producing the same amount of wet diapers. On a typical day we’re seeing anywhere from 16-20 ounces, and lately she’ll only have an ounce or two of her last bottle before bed. I’m wondering if maybe I need to introduce a stricter bottle schedule as it’s fallen pretty out of whack with her naps and meals.

We’re doing two big meals a day (lunch and dinner) with a heavy snack for breakfast and a couple of teething crackers throughout the day. Her only really solid bottle is the first of the day which is about 6 oz, then it’s a few more bottles spread throughout the day.