Measured count of redMaPPer cluster as a function of richness, for different richness bins. For each richness-redshift bin, the width of the shaded area represent the width of the richness bin, and the height correspond to the Poisson noise $\sqrt{N}$. The steeper slope of cluster counts at intermediate richness (between the second and third richness bin) for all redshift bins is primarily due to the choice of richness binning, which is not perfectly log-spaced. This steeper inner slope would be mitigated if a log-spaced richness binning were used.