# How much in interest payments since 2002 has the increase in the debt past the old debt ceiling cost the US?

Wikipedia notes several recent changes to the debt ceiling. Increases in the debt ceiling allow the Treasury to borrow more money and increase the national debt to a level higher than previously allowed by law.

August 5, 1997 5,950 +450 Pub.L. 105–33
June 11, 2002 6,400 [26] +450 Pub.L. 107–199
May 27, 2003 7,384 +984 Pub.L. 108–24
November 16, 2004 8,184 [26] +800 Pub.L. 108–415
March 20, 2006 8,965 [27] +781 Pub.L. 109–182
September 29, 2007 9,815 +850 Pub.L. 110–91
June 5, 2008 10,615 +800 Pub.L. 110–289
October 3, 2008 11,315 [28] +700 Pub.L. 110–343
February 17, 2009 12,104 [29] +789 Pub.L. 111–5
December 24, 2009 12,394 +290 Pub.L. 111–123
February 12, 2010 14,294 +1,900 Pub.L. 111–139
January 30, 2012 16,394 +2,100
May 19, 2013 16,700

How much in interest payments since 2002, has the increase in borrowing from the previous debt ceiling of \$5,950 billion to the new debt ceiling of \$16,700 billion, cost the US?

Note: Only count additional interest payments on the debt from 2002-present due to the increased borrowing limit authorized by Congress, not all interest payments since 2002.

• I may get you a more complete answer later, but since 2010 we've arguably been saving money by borrowing because the real interest rates are negative. Commented Oct 16, 2013 at 3:42
• @Avi, good point. Inflation needs to be factored into the equation. The changes in debt between 2010 and present are marginal though (only \$2.4 trillion), does that make a large enough dent in the additional interest payments when the rate was much higher (before the 2007 crash)? Commented Oct 16, 2013 at 4:41
• I'm afraid I'd have to check. Commented Oct 16, 2013 at 5:34
• As I understand this question it boils down to "what is the difference between current interest payments on government borrowing compared with 2002?" Is that a fair summary? Commented Oct 31, 2013 at 14:48
• @DJClayworth, not exactly. What is the cumulative difference in interest payments from the additional debt above the 1997-2002 debt ceiling of \$5.950t? I am only interested in the additional interest paid on debt above the previous debt ceiling, not the interest in the entire debt, nor a single year comparison. Commented Oct 31, 2013 at 15:10

Changes in the debt ceiling have no direct effect on the amount of interest paid. Only when the permissions granted by the debt ceiling are utilized to create actual debt does interest become payable. Therefore we will estimate the increase in interest payments since 2002 due to increases in the amount of borrowing.

Changes in interest paid depends on two things - changes in interest rates and changes in amount borrowed. We will try to factor out the first by considering the fraction of the debt for any year that is above the 2002 level. it is assumed that the same fraction of the interest paid is due to the debt level above the 2002 level. Dollar amounts are in billions.

Year   Debt   % above 2002     interest     due to post-2002 debt
2002   \$6,228       0%           \$332               \$0
2003   \$6,783       8%           \$318              \$25
2004   \$7,379      15%           \$321              \$48
2005   \$7,933      21%           \$352              \$74
2006   \$8,507      27%           \$405             \$109
2007   \$9,008      31%           \$429             \$133
2008  \$10,025      39%           \$451             \$175
2009  \$11,910      48%           \$383             \$184
2010  \$13,562      54%           \$414             \$224

I'll leave adding up the final column as an exercise for the reader.

A fairly large factor we have had to leave out is inflation (which reduces the impact of the interest and the debt) . We also have not cross-referenced this with GDP changes, or with increases in government income. Both generally increase the governments ability to pay interest on the debt.

NOTES

1. Debt figures are from Wikipedia.
2. Interest figures are from the Treasury
• +1 this is what i was looking for. You mght want to reconsider the GDP comment about ability to "service the debt". It gives the impression that the US intends to repay the principal. CBO projections for the last 10+ years have estimated that the defict would be eliminated (hasn't happened since Clinton) and for the next 10+ years we are estimated to keep increasing the deficit. Commented Oct 31, 2013 at 17:44
• You should definitely recalculate with inflation, particularly given how low interest rates have become relative to inflation recently. Commented Oct 31, 2013 at 22:48
• The figures are referenced. Please feel free to use them. Commented Nov 1, 2013 at 14:22

First, it's about the actual debt not the debt ceiling and second as a frame challenge to the "cost the US" phrase, you'll have to take into account positive effects from increased borrowing (a higher tax base for example) and inflation in order to determine effective costs to the US. It's not like the US government took money and simply burned it or threw it away. Instead there will have been a positive contribution to economic growth from the increased spending as well.

It may well be that any cumulative influence from increased borrowing on government finances has been actually positive not negative. See for example the famous work of Keynes that strongly advises taking on new debt in certain situations (probably because it fiscally is a better solution). On the other hand increased debt can also increase interest rates which would even affect existing debt, not only new debt. Additionally, inflation reduces the effective borrowing rate making it negative sometimes. A dollar in 2002 and one in 2022 is simply not the same (even though they have the same name) so adding them up means adding up different things. Higher numbers over time are expected from inflation alone even though they don't mean higher costs. In any case an accurate analysis of the long term costs of deficit spending vs. increasing taxes or spending cuts will be quite complex.

It will also depend on the specific circumstances with positive contributions (negative effective costs) in some circumstances in negative ones in others. There is no simple general answer unless you are only interested in some accounting aspects like interest paid without others like taxes collected or the model behind all of these. For example negative effective central bank interest rates aren't unheard of.

I took the figures referenced by DJClayworth and updated up to 2014 numbers and included inflation.

Year Debt % above 2002 interest due to post-2002 debt Cumulative Inflation Adj Debt Adj % above 2002 Adj Interest Adj due to post-2002
2002 \$6,228 0% \$332 \$0 - - - - -
2003 \$6,783 8% \$318 \$26 2.3% \$6,627 6% \$311 \$19
2004 \$7,379 16% \$321 \$50 5.0% \$7,010 11% \$305 \$34
2005 \$7,933 21% \$352 \$76 8.6% \$7,251 14% \$322 \$45
2006 \$8,507 27% \$405 \$108 12.1% \$7,478 17% \$356 \$59
2007 \$9,008 31% \$429 \$132 15.3% \$7,630 18% \$363 \$67
2008 \$10,025 38% \$451 \$171 19.7% \$8,050 23% \$362 \$82
2009 \$11,910 48% \$383 \$183 19.3% \$9,611 35% \$309 \$109
2010 \$13,562 54% \$414 \$224 21.2% \$10,687 42% \$326 \$136
2011 \$14,781 58% \$454 \$263 25.0% \$11,086 44% \$341 \$149
2012 \$16,059 61% \$359 \$220 27.6% \$11,627 46% \$260 \$121
2013 \$16,732 63% \$415 \$261 29.5% \$11,796 47% \$293 \$138
2014 \$17,810 65% \$430 \$280 31.6% \$12,182 49% \$294 \$144

In actual dollar terms the US has paid a cumulative \$1,993B in interest for solely post-2002 debt. Adjusted for inflation this number is \$1,103B.

Also adjusted for inflation, however, the interest the US pays on its debt has actually dropped 11% since 2002 unless I botched the math.

I would be eager to see someone take change in GDP/government revenue over this time period to see, adjusted for inflation, what % of the budget goes to interest now as opposed to 2002.

Debt source

Interest source

Inflation source

• Export from Excel as fixed-width text (rather than CSV). Then paste here. Select the whole block and either hit Ctrl+K or click the Code button. That should work, although I don't use Excel and can't test it at the moment. Commented Jun 8, 2018 at 20:37

It could be argued that it didn't cost anything between 2002 and 2022, because the ratio of interest payments to GDP has been continuously lower during that time compared to the first quarter of 2002:

With interest rates going up and the government continuing to increase the debt ceiling things are likely to change, but so far the interest payments have been sustainable. The Congressional Budget Office projects that things will become much worse within this decade:

• Does not answer the OP's question since, whatever the debt is, it would cost less if it was lower. Commented Jan 25, 2023 at 21:43

A frame challenge: the debt ceiling doesn't increase debt, it enables the Treasury to borrow money to pay existing debt.

If the government wants to buy a widget for 10, it takes on a debt of 10. How much and of what the government buys is the budget, so it is the budget that takes on debt.

When the US government has a debt (owes money), it pays the debt. Aside from a minor technical mishap, the US government has never failed to pay its debts. But contemporary tax policy brings in less money than the debts taken on by budget policy.

Policy is to borrow from others to service this shortfall. Doing so means ensuring we pay our bills on time and establishing clear terms in our debts. Not doing so won't erase the debt - we would still owe the debt, but we also would have to deal with not paying the debt.

Servicing the debt does incur interest payments, but defaulting incurs other costs (late payment fees, worse vendor terms, legal cases, seizure of assets, etc). Entities that don't pay their bills don't survive. Defaulting is typically substantially more expensive than servicing debt.

As such, it's not the debt ceiling that sets debt, it's the budget. And tax policy decides what we pay off. The numbers may still be interesting, but it's budget vs revenue that describe the debt you're looking for, not debt ceiling.