Percentage of mass for C and P/D-type asteroids (DeMeo & Carry 2013) and the theoretical erosion rate due to the sublimation of water ice (Schorghofer 2008) as a function of the semi-major axis. For the calculation of the theoretical loss rate, we assumed a spherical shape, a geometric albedo of 0.05, zero obliquity, and an eccentricity of 0.145 (Morbidelli et al. 2015). The abrupt decrease in the fraction of P/D type asteroids (and conversely the abrupt increase in the fraction of C-types) occurs exactly where the erosion rate due to water sublimation becomes significant.