Weight and food oz

Hey mommas I know this topics been discussed before, but my son was high on the chart and despite his increase in formula he keeps dropping now, he went from birth 98% and dropped to 50 and stayed there for a while but the last few visits he keeps dropping he’s now at 18%... he’s drinking about 34oz a day and weighs 13.1 lb, he is 15 weeks old. How much do you littles weigh and what is the age and amount they are drinking? If you have a picture, let share our little cuties💙💙💙