In a time of unprecedented fiscal stimulus, one would think that the US Treasury would at least be able to afford a recent version of excel or at least calculators. But one would apparently be wrong, because a quick look at the Treasury Direct website's disclosure of monthly and annual interest paid on Treasury debt reveals something odd.
Did you spot it?
If not, add across the individual monthly totals and what you should get is full fiscal year total of $517,640,843,766.42. Instead, the stated number is some 30% lower, or $368,102,426,277.71, which would have been appropriate 15 years ago, but certainly not now.
We have asked the Treasury whether this kind of "non-GAAP" math is used elsewhere, like for example in calculating the total amount of US debt, which is now a record $27.05 trillion having surpassed $26 trillion on Oct 1, but if the US authority which literally prints money can't afford calculators, we wouldn't hold out too much hope for computers or other email-enabled devices.