The cumulative number counts all stars and WDs with proper motion (⁠|$\mu$|⁠) larger than a given value plotted in the x-axis. For comparison, the orange-dashed line shows the counts of |$N(\gt \mu)\propto \mu ^{-3}$| that is an expected behaviour for objects with uniform number density and constant tangential velocity (see the text for details). The black dashed line represents a proper motion cut at 130 mas yr|$^{-1}$| which we impose for our analysis.