Competing Currencies: Back to the Future?

Sometimes, an emerging or rapidly changing currency experiences a period in which it competes with a second currency as a medium of exchange. The competing currencies are not like quarters and dollar bills, where the relative price is fixed, or like checks and dollar bills, where the unit of account is always the same. During an episode of dual currencies, prices are often denominated in each currency, and the relative price of an item fluctuates as the advantages offered by a particular currency change.