A simple semi-empirical relation is proposed to predict depolarization statistics on earth-space paths from rain-attenuation data for any given polarization and elevation angle, and for frequencies from 10 to 30 GHz. This formula is first justified by theoretical calculations, and then by extensive comparisons to measured data which show good agreement. In contrast to the CCIR approximate formula, the frequency dependence has been revised to be 20 log (

), and predictions of unrealistically large cross-polarization discriminations have been avoided by using a two-tier Ganssian distribution of the raindrop canting angle.