In the last five years, the Secret Service has made 29,000 arrests for counterfeiting and seized $295 million in counterfeit money--still only a fraction of the amount in circulation. Working with the U.S. Treasury Department, the Secret Service ensures that the design of U.S. currency is always evolving. The $20 bill has changed 10 times since 1928, when Andrew Jackson first appeared on the front. Changes almost always involve adding design and structural details to the bills to make them hard to replicate and easy to distinguish from fakes.