It could be. The part of economics which deals with this stuff is the Optimum Currency Area Theory. Basically, if different regions respond differently to shock

It could be. The part of economics which deals with this stuff is the Optimum Currency Area Theory. Basically, if different regions respond differently to shocks, they might prefer to have different currencies. And apparently someone posted a link on Wikipedia to an article from the Chicago Fed that suggests that there are different response areas in the United States. Link : http://www.chicagofed.org/digital_assets/publications/working_papers/2001/Wp2001-22.pdf http://www.chicagofed.org/digital_assets/publications/workin...