Glossary

Drafted with AI assistance from official sources; checked against the sources listed below.

Plain-English definitions of the terms used across 500metrics. Each entry says where the number appears on this site. Terms are defined as the US Treasury uses them; where common usage differs, the entry says so.

Allotted at high

The share of bids made at exactly the high yield that Treasury accepted. Bids at the high yield are filled only in part when there are more of them than the amount still to be filled. A low share means many bids sat right at the cut-off. See: every auction page.

Auction announcement

Treasury's notice, published a few days before an auction, of the amount on offer, the auction and issue dates, the closing times for bids and the security's terms. The announcement is the authority for each auction's rules. See: How a Treasury auction works.

Bid-to-cover ratio

The amount bid for divided by the amount accepted at a Treasury auction, leaving out the Federal Reserve's SOMA add-on. A ratio of 2.5 means bidders asked for two and a half times what was sold. Published from September 1994. Only comparable between auctions of the same term. The latest ratio and its history: Bid-to-cover ratio in Treasury auctions. See: How to read a Treasury auction result.

Cash management bill

A Treasury bill sold outside the regular calendar, for an irregular term, to cover a short gap in Treasury's cash. Their results are on one page for all cash management bills.

Competitive bid

A bid that names the lowest yield (for bills, discount rate; for floating rate notes, discount margin) the bidder will accept. One bidder can win at most 35% of the amount on offer, less any position it already has in the security. See: How a Treasury auction works.

Coupon rate

The fixed annual interest rate a note or bond pays, in two payments a year, on its face value. Treasury sets it after the auction, in eighths of a percentage point, at the rate that prices the security closest to, but not above, face value at the high yield. See: How a Treasury auction works.

CUSIP

The nine-character identifier of a security. Every Treasury bill, note and bond has one; a reopening keeps the original's. 500metrics does not publish CUSIPs. To find an auction in Treasury's own results, use its term and auction date, which every 500metrics auction page shows.

Daily Treasury Statement

Treasury's daily report of its cash, deposits, withdrawals and debt, published at 4 p.m. Eastern time on the next business day. Table III-C gives the figures for the debt limit. See: Room under the US debt limit.

Dealer takedown

Market shorthand for the share of an auction awarded to primary dealers. Because dealers take what other bidders do not, a high takedown is commonly read as thin outside demand. See: How to read a Treasury auction result.

Debt held by the public

Federal debt owned by anyone other than federal government accounts: investors in the US and abroad, banks, funds, state and local governments and the Federal Reserve. See: Room under the US debt limit.

Debt limit

The most the Treasury is allowed by law to owe at one time, also called the debt ceiling. Only Congress can raise or suspend it. On 30 September 2026 it stood at $41.104 trillion. See: The US debt limit, explained.

Debt limit suspension

A law that lifts the debt limit until a set date. The day after, the limit comes back at the amount of debt then outstanding. A suspension expires; a limit does not. See: The US debt limit, explained.

Debt subject to the limit

The part of total public debt that counts toward the debt limit. It leaves out a little under $200 billion, mostly unamortized discount. The room left is measured from this figure, not from total debt. See: Room under the US debt limit.

Debt to the Penny

Treasury's daily total of public debt outstanding, split into debt held by the public and intragovernmental holdings, with history from April 1993. It is total debt, not debt subject to the limit.

Direct bidder

A bidder other than a primary dealer that submits a competitive bid straight to Treasury for its own account, such as a large bank, pension fund or asset manager. See: How to read a Treasury auction result.

Discount margin

The margin over the index rate that floating rate note auctions are bid and quoted in instead of a yield. At a new issue the high discount margin becomes the note's fixed spread; at a reopening the spread stays and the margin sets the price.

Discount rate

For a Treasury bill, the discount from face value as a share of face value, scaled to a 360-day year. Bill auctions are bid in it. Lower than the investment rate for the same bill. The latest bill rates side by side: T-bill discount rate vs investment rate. See: Bills, notes, bonds, TIPS and FRNs.

Extraordinary measures

Accounting steps, allowed by law, that let Treasury keep paying for a time once debt reaches the debt limit, mainly by pausing new investments of certain federal retirement funds. The funds are made whole after the limit is lifted. See: The US debt limit, explained.

Face value

The amount a security repays at maturity, also called par. Prices are quoted per $100 of face value.

Fiscal year

The federal budget year, from 1 October to 30 September, named for the year it ends in. Fiscal year 2026 ended on 30 September 2026. See: Interest on the national debt this fiscal year.

Floating rate note

A two-year Treasury note whose interest resets every week to the latest 13-week bill auction rate plus a fixed discount margin. Often shortened to FRN. The latest FRN auction and its margins: Treasury floating rate notes (FRNs), explained. See: 2-year frn auctions.

Gross interest expense

Interest accrued on all Treasury debt, including interest credited to federal trust funds. Treasury publishes it monthly. It is larger than net interest, and the two are never swapped on 500metrics. See: Interest on the national debt, explained.

High yield

The highest yield Treasury accepted at an auction, and so the yield every successful bidder gets. For bills the equivalents are the high discount rate and the high investment rate; for TIPS it is a real yield. The latest high and median yields: High yield vs median yield. See: every auction page.

Index ratio

For a TIPS, the consumer price index on a given day divided by the index on the security's dated date. Principal and auction prices are multiplied by it, so a ratio above 1 means inflation has raised the principal. See: How to read a TIPS auction result.

Indirect bidder

A bidder that places its competitive bid through a primary dealer or another direct submitter, including foreign central banks bidding through the Federal Reserve Bank of New York and many investment funds. The results do not say who they were. The latest indirect share and its history: Indirect bidders in Treasury auctions. See: How to read a Treasury auction result.

Intragovernmental holdings

Federal debt owned by federal government accounts, mostly trust funds such as Social Security and the military and civil service retirement funds. These are special nonmarketable securities that never trade. See: Room under the US debt limit.

Investment rate

For a Treasury bill, the return on the price paid, scaled to a 365-day year. Comparable with note and bond yields, and higher than the bill's discount rate. The latest bill rates side by side: T-bill discount rate vs investment rate. See: Bills, notes, bonds, TIPS and FRNs.

Investor class

Treasury's separate monthly breakdown of who was awarded each auction, by type of investor (for example investment funds, foreign and international, dealers). It is published after the auction results and in broader groups than a reader may expect.

Issue date

The day a security sold at auction is delivered and paid for, a few days to a few weeks after the auction. Also called the settlement date.

Marketable debt

Treasury securities that can be bought and sold in the market after issue: bills, notes, bonds, TIPS and floating rate notes. Savings bonds and intragovernmental securities are nonmarketable. See: US Treasury debt maturing in the next 12 months.

Maturity date

The day a security repays its face value and stops paying interest.

Maturity wall

The amount of Treasury debt coming due over a stretch of time, usually the next 12 months. See: The Treasury maturity wall, explained.

Median yield

The yield at or below which half of the amount of accepted competitive bids was made. Treasury publishes it with the high and low yields. The latest high and median yields: High yield vs median yield.

Monthly Statement of the Public Debt

Treasury's month-end list of every security outstanding, with its amount and maturity date, published on the fourth business day of the next month. Often shortened to MSPD. It is the source of the maturity calendar. See: US Treasury debt maturing in the next 12 months.

Net interest

The budget's measure of interest cost: interest paid to holders outside the government, less interest the government earns. Reported in the Monthly Treasury Statement and by the Congressional Budget Office. Smaller than gross interest expense. See: Interest on the national debt, explained.

Noncompetitive bid

A bid, of up to $10 million, that agrees to take whatever yield the auction sets. Accepted in full before any competitive bid. It is how most individuals take part. See: How a Treasury auction works.

Offering amount

The amount Treasury announces it will issue at an auction. Federal Reserve SOMA add-ons come on top of it.

Primary dealer

One of the banks and broker-dealers that trade directly with the Federal Reserve Bank of New York. Primary dealers are expected to bid in every Treasury auction, so they take whatever other bidders do not. The latest dealers' share: What is a primary dealer?. See: How to read a Treasury auction result.

Quarterly refunding

Treasury's borrowing announcement each quarter, usually on the first Wednesday of February, May, August and November, setting out the sizes of the coming note and bond auctions. The 10-year note and the 30-year bond are new issues in those months. See: What is the Treasury quarterly refunding?.

Real yield

A yield after inflation. TIPS auction results are real yields, so they are not comparable with the nominal yields of ordinary notes and bonds. See: How to read a TIPS auction result.

Reopening

An auction of more of a security that already exists, with the same maturity date, coupon and CUSIP. Treasury labels it by the time left ("9-Year 11-Month"); 500metrics files it under its original term ("10-year note, reopening"). The latest reopening and its term: What is a Treasury reopening?. See: Bills, notes, bonds, TIPS and FRNs.

Rollover

Paying off maturing securities with cash from newly issued ones. It is how Treasury handles most maturing debt. The word also covers an investor putting the proceeds of a matured bill into a new one. See: The Treasury maturity wall, explained.

Room left

The debt limit minus debt subject to the limit: how much more Treasury may borrow. It is room to borrow, not a measure of cash. Also called headroom. See: Room under the US debt limit.

Single-price auction

An auction in which every successful bidder pays the same price, set by the high yield, whatever yield each one bid. All Treasury auctions work this way.

SOMA

The System Open Market Account, where the Federal Reserve keeps its Treasury securities. When its holdings mature, the Fed can reinvest in new securities at auction. Those amounts, SOMA add-ons, come on top of the offering amount, are awarded at the high yield, and are left out of the bid-to-cover ratio.

Stop-through

An auction whose high yield was below the when-issued yield just before the deadline: a negative tail. 500metrics does not publish it.

Tail

The high yield minus the when-issued yield just before bidding closed. Positive when Treasury had to accept a higher yield than the market expected. It needs licensed market quotes, so 500metrics does not publish it; figures elsewhere come from each publisher's own feed. The two official stand-ins, with the latest figures: What is a Treasury auction tail?. See: How to read a Treasury auction result.

Tendered and accepted

Tendered is the total amount bid for at an auction; accepted is the amount awarded. Their ratio, without SOMA, is the bid-to-cover ratio.

TIPS

Treasury Inflation-Protected Securities: notes and bonds of 5, 10 and 30 years whose principal rises and falls with the consumer price index. They pay a fixed coupon on that adjusted principal. The latest TIPS auction and its real yield: What are TIPS?. See: 10-year tips auctions.

Total public debt outstanding

All federal debt issued by Treasury: debt held by the public plus intragovernmental holdings. On 30 September 2026 it was about $40.17 trillion.

Treasury bill

A Treasury security of one year or less (4 to 52 weeks) that pays no coupon. It is sold below face value and repays face value at maturity. See: 13-week bill auctions.

Treasury bond

A Treasury security of more than 10 years, today 20 or 30 years, paying a fixed coupon every six months. See: 30-year bond auctions.

Treasury General Account

Treasury's cash account at the Federal Reserve, from which the government's payments are made. Its balance is in the Daily Treasury Statement. Often shortened to TGA. See: Room under the US debt limit.

Treasury note

A Treasury security of 2 to 10 years (today 2, 3, 5, 7 and 10), paying a fixed coupon every six months. See: 10-year note auctions.

Unamortized discount

The part of a security's discount from face value that has not yet accrued as interest. It is the main item that makes debt subject to the limit smaller than total public debt.

Weighted average maturity

The average time left until marketable debt matures, weighted by amount. A shorter average means more debt is repriced at new rates each year. See: The Treasury maturity wall, explained.

When-issued

Trading in a security after its auction is announced but before it is issued. The when-issued yield just before the deadline is the market's expectation that the tail is measured against.

X-date

The projected first day Treasury could no longer pay all of the government's obligations in full and on time once extraordinary measures and cash run out. Always someone's projection; 500metrics shows published ones with their dates and makes none of its own. See: The US debt limit, explained.

Yield

The annual return on a security bought at a given price and kept to maturity, counting both coupons and any gap between the price and face value.