I'm curious whether one can numerically calculate the effect that counterfeiting has on an economy.
As I understand it, counterfeiting essentially amounts to theft of the wealth of everybody holding units of that currency. For example, say you have an economy with 100 units of currency currently circulating. Bob creates 100 fake units of currency. If he does nothing but leave them in his safe, then the economy is unaffected. However, if he spends all of them, he will get goods and services in exchange for nothing of value. This is the theft. Him introducing his 100 fake units into the economy doubles the money supply, which will eventually more or less lead to a doubling in the price of everything (but not necessarily).
So now, if Dave had 10 units of currency his purchasing power was X. However, after the counterfeiting and doubling of the money supply and thus more or less doubling of prices, his purchasing power is X/2. Likewise for anybody who was holding that currency.
So, is it correct to say that in an economy with X currency units, counterfeiting and spending Y fake units is equal to theft of Y/(X+Y) of the wealth of the economy?
e.g. Given 100 legit units and counterfeiting and spending 200 units, 2/3rds of the wealth was stolen?
If not then what is the effect?