If the government ever tries to eliminate the $100 bill, it would take a long time to get rid of them all.

Former Treasury Secretary Larry Summers floated the idea this week of killing the $100 bill to fight crime and corruption. Money launderers and terrorists abroad, for example, prefer large bills to quickly move cash illegally.

The Treasury says it has no plans to follow Summers’s suggestion, but it would be a daunting task. Some 10.8 billion $100 bills were in circulation at the end of 2015 and most were held outside the United States. Those notes represented nearly $1.1 trillion in value.

Bad guys don’t have a monopoly on $100 bills, either. U.S. currency is a fail-safe for governments and citizens of foreign nations, especially when their economies go sour. They hoard dollars during crises such as the financial panic of 2008 when their own currencies lose value.

A Federal Reserve study a few years ago estimated that two-thirds of all $100 bills are held by foreigners.

Many ordinary Americans also use $100 bills legitimately, such as giving graduation gifts or keeping cash tucked away at home for emergencies.

Yet some studies also suggest C-notes are popular for under-the-table work that escapes government taxation. Almost 20% of all taxable income in the U.S. goes unreported, one study shows.

Is the $100 Bill Endangered?

In any case, the $100 bill is more popular than ever. It represents 28% of all U.S. notes in existence, up from 14% in 1995. The only note that has wider circulation is the $1 bill — and just barely.

What’s more, demand for U.S. currency of all denominations has soared despite an increasing shift toward electronic money in the form of credit cards, debit cards, PayPal, Bitcoin and the like.

The amount of bills in circulation has jumped 244% in the past 20 years, reaching a value of $1.39 trillion at the end of 2015. That easily outstrips a 134% increase in gross domestic product during the same span.

Even if the government stopped printing new $100 bills, most existing ones would probably remain in circulation overseas.

Perhaps getting rid of the $100 bill is an idea worth considering, but doing so would give the government more power over the economy — and regular citizens and criminals alike.

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