The history of currency

This very useful site may help provide a perspective on a concept that for some reason appears to be very difficult for most people to understand: a monetary unit is, on average, a short-lived thing:

The median age for a live currency is 37 years and at least one, the Zimbabwe dollar, is in the throes of hyperinflation. Excluding the early paper currencies of China up until the 15th century and the majority of paper currencies that existed in China until 1935, there are 609 currencies no longer in circulation. Of these, at least 153 were destroyed as a result of hyperinflation caused by over-issuance. The remainder were revalued, destroyed by military occupation/liberation, renamed for political reasons, or were converted to another currency. The median age for these currencies is only seventeen years.

This list, of course, is by no means perfect. For example, the present dollar is by no means identical to the 1792 dollar, which was defined by the Coinage Act of that year and specified a dollar to be 371.25 grains (24.75 grams) of silver. At today’s silver price, that 1792 dollar is worth 8.18 in current dollars.

Regardless, it’s a near-certainty that most of us will live to see the U.S. dollar replaced by another currency. On the other hand, keep in mind that nothing ever goes straight to zero and the dollar may well continue to strengthen against other paper currencies in light of the current deflation.