Actually that would break so many things (the cent as the smallest unit in law and in custom where that is currently the case) that governments may by preference issue a whole new currency instead of stir that pot.
> https://www.law.cornell.edu/uscode/text/31/5101 says "United States money is expressed in dollars, dimes or tenths, cents or hundreths,[1] and mills or thousandths. A dime is a tenth of a dollar, a cent is a hundredth of a dollar, and a mill is a thousandth of a dollar."
> [1] So in original. Probably should be “hundredths,”.
About the only time you see values given in mills is with gas prices, like $4.999/gal, though often denoted as tenths of a cent. It's also indirectly used in property taxes.
This year on our local ballot there is a tax levy to approve an increase to the property tax by 5 mills per 100,000 dollars of assessed property value. Allegedly allowing them to raise a few million over the next 10 years to pay off an addition to the school.
> https://www.law.cornell.edu/uscode/text/31/5101 says "United States money is expressed in dollars, dimes or tenths, cents or hundreths,[1] and mills or thousandths. A dime is a tenth of a dollar, a cent is a hundredth of a dollar, and a mill is a thousandth of a dollar."
> [1] So in original. Probably should be “hundredths,”.
About the only time you see values given in mills is with gas prices, like $4.999/gal, though often denoted as tenths of a cent. It's also indirectly used in property taxes.