Residuals to the local polynomial regression plotted in Fig. 1 (solid line in that figure) as a function of GC age to relaxation-time ratio. Core-collapse is found to occur for a ratio of about 5 to 10 depending on the mass spectrum and initial concentration (see simulations in the following). The superimposed local polynomial regression line (dashed) shows a peak in this age range. For comparison, the ticks on the vertical axis at the right side of the plot show (from bottom to top) the first quartile, the median, and the third quartile of the distribution of residuals.