That would depend on your baby's age. But basically in my case, my baby is 16 mons old, pedia said that 5-6 bottle of milk is most likely what my child will consume in a day. And she's right. Baby can finish 3 bottles throughout the day and 2-3 bottles (btw, 7 oz each) during night time. So doing the math now, a 1.6kg formula is consumed by lo within 12 days :)
My nephew went through about 4 to 5 cans after my cousin (his mom) weaned him! It's totally normal. :)
my toddler consume 6kg of formula in a month