It was essentially a tax on paper money. Most transactions were conducted over an indexed value, there were many at the time: ORTN, OTN, URV was the last one for the transition to the current coin. And yes, lots of US$ 100 bill stacks, when you didn't want to report the transaction :)

The biggest problem was, contracts had to be written using the national currency, so they got obsolete very fast. For example, the government did some purchase and then paid 4 months late; it was effectively paying half. So the prices you had to put on paper had to guess the probable delay and compensate for.