Never empty bag

Let's say in a week,
7 tops + 7 bottoms + 7 under wears = 21,
Then, 3 (weekends clothes or kai kai clothes) + 4 (stay home clothes) + 3 bottoms = 9
So one person = 30 pieces of laundry per week and two will be 60 pieces.
I am doing 3 times laundry per week which means each time 20 pieces.....
AND my laundry bag still never empty ....... headache....

P/S : ohh I still have two pieces of towels to change per week, 1 set of bed sheets and cover in a fortnight.