What would be the appropriate word opposite to "excess" in the following sentence?
The excess number of particles in the box is negative.
I want to write about a depletion of particles rather than an excess. Something like:
The depletion number of particles in the box is positive.
"Depletion number" does not sound right to me.
The context is an advanced physics text, where this "excess number" or "depletion number" is represented by a variable (an integer) that appears in mathematical formulas.