Biography & Early Wealth Journey

"It could be driven by a global fear of negative interest rates in Europe and Japan, or it could be a savings vehicle for U.S. households worried about another financial crisis, or it could be driven by more demand from the global underground economy."

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"Underground economy" is a pretty nifty euphemism for crime and corruption, and the $100 bill remains a favored unit of currency for criminals and the otherwise corrupt all over the world. As DataTrek Research's Nicholas Colas put it to CNBC:

Primary Income Streams & Multi-Million Contracts

"It has nothing to do with the U.S. economy and nothing to do with interest rates…There's certainly enough evidence to say it is an enabler of corruption, but it is also a way for people to keep assets outside of the financial system albeit in a kind of bulky way."

While the total number of hundreds in circulation has doubled since the US financial crisis, the surge in hundreds goes back even further, with some tracing it back to the US invasion of Afghanistan or even the Gulf War, when war-torn regions turned to US currency over local currencies as a way to bring about more economic stability. If that surprises you, a study from last year by the Federal Reserve Bank of Chicago will likely surprise you even more: It found that 60 percent of all US bills are currently somewhere overseas, including a whopping 80 percent of $100 bills. At the same time, rises in the use of digital payment services have led to declines for smaller denominations, something of a perfect storm for Franklin to surpass the other dead presidents at the top of the heap.