The current value of this coin is determined by what someone is willing to pay for it. Ask yourself how much did I pay for this coin? That is its current value, however the next person may not be willing to pay that amount LOL .. could not resist
Well you have the Emperor's name and date range a lot of the early coins weren't issued with a specific year and covered the entire period of the reign.
You might want to check out some coin dealers who specialize in ancient coins and see what that one goes for.