A useful lesson in monetary economics from the NYTIMES:
A Cashless Economy in Zimbabwe? With Little Cash, There’s Little Choice
http://www.nytimes.com/2016/11/04/world/africa/zimbabwe-robert-mugabe-cash-debit-cards.html
http://www.nytimes.com/2016/11/04/world/africa/zimbabwe-robert-mugabe-cash-debit-cards.html