The mass flow rate is primarily dependent on the cross-sectional area formula_10 of the nozzle throat and the upstream pressure formula_11, and only weakly dependent on the temperature formula_12. The rate does not depend on the downstream pressure at all. All other terms are constants that depend only on the composition of the material in the flow. "Although the gas velocity reaches a maximum and becomes choked, the mass flow rate is not choked". The mass flow rate can still be increased if the upstream pressure is increased as this increases the density of the gas entering the orifice.