For fainter magnitudes, the supplemental list documentation states that, ... of the perhaps 20,000 stars between V=7.5 and V=8.5 only a few hundred are missing from PPM.
對於更暗淡的恆星，在補充清單中指出： ... 在V=7.5和V=8.5之間的20,000顆恆星，PPM可能只遺漏了數百顆。