National debt hits $21 trillion

Under the law passed in February, the government will not face any borrowing limit until March 1, 2019. At its current pace, the government is on track to add at least $1 trillion to the national debt by then.

For example, the debt grew by more than half a trillion dollars in the six weeks since the debt ceiling was lifted on Feb. 9.

A large part of the national debt reflects the federal budget deficit, or the amount of spending above the revenues collected by the government. But the debt is rising faster than the amount of the budget deficit, as it also reflects things like federal lending for student loans and mortgage programs.