LEED asks that the baseline and projected water use be evaluated at 60 and 80psi. How can we account for the fact that the pressure won't be that high?

Th project is a luxury hotel, which plans to use showerheads that have a 50L/min (13gpm) at 80psi. The water pressure in the bathrooms will be set at 44psi max, which would bring the showerhead max flow down to 7.4gpm. It remains too high but it would make a big difference to our water use value.

Would we have to find the equivalent standard flows at 44psi in order to compare baseline and projected flows?