Mass functions of young clusters in the Antennae and LMC (upper panel) and old globular clusters in the Milky Way and Sombrero (lower panel), as described in the text. The smooth curves in both panels are from the simple evaporation model, Equation (18) with μ _ev = 2 × 10 ⁻⁵ M _☉ yr ⁻¹, at ages τ = 0, 1.5, 3, 6, and 12 Gyr. Note the excellent fit of the model to the data at both τ = 0 (upper panel) and τ = 12 Gyr (lower panel).