Proper motions in Galactic longitude (top) and latitude (bottom) as a function of Galactic longitude for the sample of 385 423 B-stars described in the text. The lines show the proper motions predicted from the rotation curve model parameters resulting from the fit to the data for stars at 500 pc (dashed line) and 2000 pc from the Sun (solid line, close to the median distance of stars in the sample).