fake bills

Counterfeiting of the currency of the United States is widely attempted. According to the United States Department of Treasury, an estimated $70 million in counterfeit bills are in circulation, or approximately 1 note in counterfeits for every 10,000 in genuine currency, with an upper bound of $200 million counterfeit, or 1 counterfeit per 4,000 genuine notes.
However, these numbers are based on annual seizure rates on counterfeiting, and the actual stock of counterfeit money is uncertain because some counterfeit notes successfully circulate for a few transactions.

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