While we are all washing up ...
Beloved Spouse and I, and the cat, go through about 10 USG of fresh water a day, at full "motorhome" consumption. That is, two showers, drinking, meal prep and washing, and way too much coffee.
On any kind of water rationing, e.g. bathing every other day, you can drop that to 5 USG without much pain.
Our Tiger had about 40 USG and the 917 has about 100 USG. For us, this is the height of luxury. We crossed the Sahara with less than 30 USG total. (And yes, we took three showers when we got to El Golea!)