This is a blurb from an NPR story. The above image was taken just before the numbers grew too large.
It's official, the national debt clock has run out of numbers. The giant sign in New York City changes constantly as the federal debt increases. It was put up years ago by a real estate developer horrified that the debt was approaching $3 trillion. Some years ago, the clock stopped when the U.S. started running a surplus. But now it's running again, and when the debt struck $10 trillion recently, the owners had to improvise an extra number one.