Mysterious surge in $100 bills in circulation has officials scratching their heads

The amount of $100 bills in circulation is surging. And it's leaving some economists scratching their heads.
The number of outstanding U.S. $100 bills has doubled since the financial crisis, with more than 12 billion of them across the world, according to the latest data from the Federal Reserve. C-notes have passed $1 bills in circulation, Deutsche Bank chief international economist Torsten Slok said in a note to clients this week.

A 2018 research paper from the Federal Reserve Bank of Chicago estimates that 60 percent of all U.S. bills and almost 80 percent of all $100 bills are now overseas. That's up from 15 to 30 percent around 1980, according to research from Federal Reserve Board economist Ruth Judson. She found that economic and political instability contribute to this demand.

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