  Attempts to accurately measure the monetary velocity or related properties of
bitcoin used in transactions have often attempted to either directly apply
definitions from traditional macroeconomic theory or to use specialized metrics
relative to the properties of the Blockchain like bitcoin days destroyed. In
this paper, it is demonstrated that beyond being a useful metric, bitcoin days
destroyed has mathematical properties that allow you to calculate the average
dormancy (time since last use in a transaction) of the bitcoins used in
transactions over a given time period. In addition, bitcoin days destroyed is
shown to have another unexpected significance as the average size of the pool
of traded bitcoins by virtue of the expression Little's Law, though only under
limited conditions.
