How to use:
Input the number of people in the building/area and the water cost per 1,000 litres in the top two boxes (grey).
The amounts of water (litres) and money you can save by switching to a vacuum system are displayed in the two lower boxes (blue).
Gallons: Multiply gallons by 3.785 to convert to liters before calculating - also divide the water price per 1,000 gallons by 3.785.