An equation is presented, which allows us to calculate the dependence of the multiplicity of the particles produced in nucleus-nucleus collisions, 〈nπ〉AA, on an experimentally measured value Q/Zpr, which is strongly correlated to the impact parameter b. The equation combines data from a wide range of projectile masses (Apr = 6-197) over a large momentum region (ppr = 4-200 A GeV/c). The possible meaning of the parameters is discussed in the context ...