From their post "The U.S. Debt Load: Big and Cheap" which I believe is a play on the country music band "Big and Rich".
Or maybe not.
We've looked at the treasury numbers a few times , the most recent was March 2012's "Of Debt and Interest Rates: This Ain't No Party, This Ain't No Disco":
1) 2.2 percent is the average interest rate on the U.S. Treasury’s marketable and non-marketable debt (February data).
2) 62.8 months is the average maturity of the Treasury’s marketable debt (fourth quarter 2011).
3) $454 billion is the interest expense on publicly held debt in fiscal 2011, which ended Sept. 30.
4) $5.9 trillion is the amount of debt coming due in the next five years.
For the moment, Nos. 1 and 2 are helping No. 3 and creating a big problem for No. 4. Unless Treasury does something about No. 2, Nos. 1 and 3 will become liabilities while No. 4 has the potential to provoke a crisis.
So we've made some progress.