How the Government Borrows

What this means

A deficit is not a thing the government can simply have. If outlays exceed receipts, the difference must come from somewhere, and the somewhere is borrowing. The Treasury sells IOUs to willing buyers, and those buyers hand over cash today in exchange for a promise of repayment later.

The IOUs come in three forms, distinguished mainly by how long they run. Treasury billsShort-term Treasury securities that mature in one year or less and are sold at a discount to face value., called T-bills, mature in a year or less; they pay no periodic interest and are instead sold for less than their face value, with the difference serving as the return. Treasury notesMedium-term Treasury securities, typically maturing in two to ten years, that pay interest twice a year. run a few years to ten and pay interest semiannually. Treasury bondsLong-term Treasury securities, typically maturing in twenty to thirty years, that pay interest twice a year. run twenty or thirty years on the same interest-paying structure.

These are sold at auctionA public sale in which competing buyers bid, and the resulting price determines the interest rate the government pays.. The government does not announce a rate and hope for takers; it announces an amount and lets bidding determine the price. Strong demand means a higher price and therefore a lower yield to the government's benefit; weak demand means the opposite. This is why bond prices and yields move in opposite directions, a relationship worth committing to memory.

Who buys, and why? Individuals, pension funds, insurance companies, mutual funds, banks, foreign governments, foreign central banks, and the Federal Reserve. Their reasons converge on three properties. Safety: Treasuries are backed by the taxing authority of the U.S. government and are treated across global finance as the benchmark for a low-risk asset. Liquidity: the market for Treasuries is among the deepest in the world, so a large holder can sell quickly without moving the price much. Predictability: the payment schedule is known in advance, which matters enormously to a pension fund that must meet obligations on a known timetable.

The trade-off is that low risk pays a low return. An investor who wants higher expected returns buys stocks or corporate bonds and accepts the risk that comes with them. Treasuries are what you buy when preserving the principal outranks growing it.

Now the second half of this benchmark, which is the subtler half. Interest rates change the government's costs even when its borrowing does not. Treasury securities mature constantly, and when they do the government typically issues new ones to replace them, a process called rolling overIssuing new debt to replace maturing debt, so the borrowing continues at whatever interest rate currently prevails.. Existing securities keep paying their original rate to maturity, but every rollover reprices at today's rate. If rates have risen, that replacement debt costs more. Multiply across a large stock of debt with a mix of maturities and interest costs climb year after year, without a single dollar of new deficit. This is why the interest line in the federal budget can grow for reasons that have nothing to do with current spending decisions.

Why it matters

Treasury yields sit underneath much of the financial system. Mortgage rates, corporate borrowing costs, car loans, and student loan rates all reference them to varying degrees. When Treasury yields move, the rate you will eventually pay on a house moves with them.

There is also a budgetary consequence that is worth understanding before anyone tries to persuade you of anything about it. Interest is a required payment. Money committed to interest is unavailable for anything else, and unlike most spending it is not subject to an annual decision. Whether the current level of that obligation is manageable is a genuine dispute, and it depends on interest rates, on economic growth, and on what the borrowing financed. Look up the current interest cost as a share of the budget yourself rather than accepting a figure from anyone, including this lesson.

Try it

1. Learn the instruments. Build a table with rows for bills, notes, and bonds, and columns for typical maturity, how the return is paid, and what kind of investor might prefer each. Explain why a money market fund would hold bills while a pension fund might hold thirty-year bonds.
2. Visit TreasuryDirect. Find the auction schedule and a recent auction result. Record the security type, the amount offered, and the resulting yield.
3. Explain the auction. In your own words, describe how competing bids determine the interest rate the government ends up paying, and explain why unusually weak demand at an auction raises the government's cost.
4. Work out the price-yield relationship. You own a bond paying a fixed annual amount. Newly issued bonds now pay more. Explain what must happen to the market price of your bond for a buyer to be willing to take it instead of a new one. State the general rule you have just derived.
5. Answer the investor question. Write a paragraph explaining why a large pension fund holds Treasuries even though stocks have historically produced higher average returns over long periods. Your answer must address obligations with known due dates.
6. List the buyers. Identify at least five distinct categories of Treasury holders and, for each, the specific reason that buyer wants safety, liquidity, or predictability. Include foreign central banks and explain their motivation.
7. Model the rollover effect. Assume a government has borrowed a fixed total, with one-fifth of it maturing each year and being replaced. Rates rise by two percentage points and stay there. Trace what happens to annual interest cost over five years, assuming no new borrowing at all.
8. State the conclusion from step 7 in one sentence, in a form that would be clear to someone who has never taken economics.
9. Consider the feedback loop. Higher interest costs increase outlays, which widens the deficit, which requires more borrowing. Describe this loop, then identify the conditions under which it does not spiral, particularly the relationship between the interest rate and the economy's growth rate.
10. Take a position honestly. Given what you found, write two paragraphs: one arguing that a large stock of federal debt is a serious constraint on future budgets, one arguing that it is manageable if borrowing costs stay below the growth rate and the borrowing funded productive investment. Then say which you find more persuasive and identify the specific evidence that would change your mind.

Check yourself