Interesting. It is actually a part of a larger text named Vriddha Gargiya Jyotisha.It seems to have been written at around 1st – 2nd century A.D. It is said to give a detailed accounts of the invasions by the Greeks and the Scythians among other things. The references to Gargiya Jyotisha in some other Puranas show that it was written earlier than atleast these Puranas.
Interestingly, it completely ignores Ramayana and avatarhood. It mentions the MahaBharata war but not by that name. On this basis, one of the articles says that this text must have been written before the epics themselves. But, Yuga Purana mentions other figures like Parasurama and Krishna.
So, if the dating of this text and its interpretation are correct, it would mean that the epics were composed after 2nd century A.D.