I am looking for trade and migration data in the Ancient Greece and
Ancient Rome eras. Especially, I am looking for the hard figures on
trade and migration among the city-states and their colonies (e.g.,
trade and migration figures between Sparta and Athens). If possible, I
would also love to have the data on any other types of interaction
among the city-states and their colonies (e.g., let?s say travel
data). Could you recommend any data source(s) for my need?

Thanks so much in advance.