Proper motion errors (in decl.) after 10 yr of LSST for a sample of 1000 randomly drawn sky positions and magnitudes, as a function of the i-band magnitude. Red points represent the scenario where no turbulence correction is applied (10 mas errors added in quadrature to the photon-noise error). Green points reduce the astrometric errors according to the performance of our turbulence reduction code (the astrometric floor is moved from 10 to 3 mas). Continuous lines are medians.