Glitch activity as a function of . Black dots represent the glitch activity (sum of all glitch sizes divided by the sum of the observation times) for all pulsars within bins of , and blue dots represent the same quantity but restricted to small glitches (Δν < 10 μHz). (Data kindly provided by J. R. Fuentes, from the glitch sample discussed in Fuentes et al. 2017.) The green and red lines represent the glitch activity in the starquake model, as given by Eq. (84), for the values b = 10⁻⁵ and b = 10⁻⁶ of the rigidity parameter, corresponding to the cases and , respectively.