Treasury bond

912810SU3 · 1.875% due February 15, 2051

Original term
30-Year
Maturity
Feb 15, 2051
Coupon
1.875%
Pays
Semi-Annual
Dated
Feb 15, 2021
First coupon
Aug 15, 2021
Priced through
Sep 10, 2026
Analyzed through
Sep 10, 2026

Statement of August 31, 2026

Amount outstanding
$88.19bn
Held stripped
$18.95bn
Share stripped
21.49%

Stripped par is held as separate interest and principal components rather than as whole securities. The Safe Rate indices deliberately do not deduct it, and the whole-market figure is published so that decision can be argued with. Market statistics.

Amount outstanding as reported by Treasury, in its Monthly Statement of the Public Debt. The Safe Rate indices weight on a different figure, float-adjusted original par, and the two are not comparable security by security. The index figures are published per holding.

Risk, September 10, 2026

Yield to maturity
5.472%
Modified duration
16.866 yr
DV01
0.0877
Convexity
364.395
Dirty price
51.981

Where its rate sensitivity sits

3M
6M
1Y
2Y
3Y
5Y
7Y
10Y
15Y
20Y
25Y
30Y
Sensitivity to a one basis point move at each point on the curve, in years. Concentrated in 11 of twelve buckets, summing to 17.111 years against a modified duration of 16.866.

Against the fitted curve

Priced 2.2 bp rich to the curve on that day, 19.70 cents per 100 of face.

That is -0.71 standard deviations from its own typical residual.

Yield to maturity, 1,396 observations

1%2%3%4%5%6%Feb 16, 2021Sep 10, 2026Feb 16, 2021Yield to maturity2.085%Apr 1, 2021Yield to maturity2.338%May 17, 2021Yield to maturity2.370%Jul 1, 2021Yield to maturity2.088%Aug 17, 2021Yield to maturity1.932%Oct 1, 2021Yield to maturity2.051%Nov 18, 2021Yield to maturity1.988%Jan 5, 2022Yield to maturity2.109%Feb 22, 2022Yield to maturity2.276%Apr 7, 2022Yield to maturity2.728%May 24, 2022Yield to maturity3.044%Jul 12, 2022Yield to maturity3.183%Aug 25, 2022Yield to maturity3.330%Oct 12, 2022Yield to maturity3.964%Nov 29, 2022Yield to maturity3.903%Jan 17, 2023Yield to maturity3.694%Mar 3, 2023Yield to maturity3.914%Apr 18, 2023Yield to maturity3.823%Jun 2, 2023Yield to maturity3.928%Jul 20, 2023Yield to maturity3.949%Sep 5, 2023Yield to maturity4.430%Oct 20, 2023Yield to maturity5.151%Dec 6, 2023Yield to maturity4.305%Jan 24, 2024Yield to maturity4.512%Mar 11, 2024Yield to maturity4.344%Apr 24, 2024Yield to maturity4.832%Jun 10, 2024Yield to maturity4.651%Jul 26, 2024Yield to maturity4.537%Sep 11, 2024Yield to maturity4.068%Oct 28, 2024Yield to maturity4.625%Dec 13, 2024Yield to maturity4.738%Jan 31, 2025Yield to maturity4.933%Mar 19, 2025Yield to maturity4.676%May 2, 2025Yield to maturity4.911%Jun 18, 2025Yield to maturity5.001%Aug 5, 2025Yield to maturity4.874%Sep 19, 2025Yield to maturity4.845%Nov 5, 2025Yield to maturity4.840%Dec 23, 2025Yield to maturity4.942%Feb 10, 2026Yield to maturity4.885%Mar 27, 2026Yield to maturity5.108%May 12, 2026Yield to maturity5.143%Jun 29, 2026Yield to maturity4.970%Aug 13, 2026Yield to maturity5.328%Sep 10, 2026Yield to maturity5.472%

Price history

1,396 trading days to Sep 10, 2026

5060708090100110Feb 16, 2021Sep 10, 2026Feb 16, 2021Close95.344Apr 1, 2021Close90.094May 17, 2021Close89.469Jul 1, 2021Close95.313Aug 17, 2021Close98.719Oct 1, 2021Close96.125Nov 18, 2021Close97.500Jan 5, 2022Close94.938Feb 22, 2022Close91.531Apr 7, 2022Close83.031May 24, 2022Close77.719Jul 12, 2022Close75.563Aug 25, 2022Close73.375Oct 12, 2022Close64.625Nov 29, 2022Close65.500Jan 17, 2023Close68.375Mar 3, 2023Close65.531Apr 18, 2023Close66.813Jun 2, 2023Close65.531Jul 20, 2023Close65.344Sep 5, 2023Close59.656Oct 20, 2023Close52.250Dec 6, 2023Close61.281Jan 24, 2024Close59.031Mar 11, 2024Close61.031Apr 24, 2024Close55.813Jun 10, 2024Close57.813Jul 26, 2024Close59.156Sep 11, 2024Close64.688Oct 28, 2024Close58.406Dec 13, 2024Close57.313Jan 31, 2025Close55.438Mar 19, 2025Close58.188May 2, 2025Close55.875Jun 18, 2025Close55.094Aug 5, 2025Close56.469Sep 19, 2025Close56.875Nov 5, 2025Close57.031Dec 23, 2025Close56.125Feb 10, 2026Close56.813Mar 27, 2026Close54.750May 12, 2026Close54.531Jun 29, 2026Close56.313Aug 13, 2026Close53.063Sep 10, 2026Close51.844
The most recent 20 trading days of prices for 912810SU3.
DateBidOfferClose
Sep 10, 202652.12552.09451.844
Sep 9, 202652.50052.46952.656
Sep 8, 202652.96952.93852.875
Sep 4, 202653.00052.96952.906
Sep 3, 202653.06353.03152.906
Sep 2, 202652.68852.65652.688
Sep 1, 202652.93852.90652.688
Aug 31, 202652.78152.75052.875
Aug 28, 202653.50053.46953.188
Aug 27, 202653.56353.53153.406
Aug 26, 202653.54753.53153.500
Aug 25, 202653.56353.53153.594
Aug 24, 202653.21953.18853.063
Aug 21, 202652.75052.71952.625
Aug 20, 202652.84452.81352.969
Aug 19, 202653.18853.15653.281
Aug 18, 202652.28152.25052.375
Aug 17, 202652.40652.37552.156
Aug 14, 202652.59452.56352.625
Aug 13, 202653.06353.03153.063

Prices are per 100 of face, from Treasury's own end-of-day file. A dash in the bid or offer column means none was posted that day.

3 auctions

A CUSIP can be auctioned more than once: Treasury reopens an existing security rather than issuing a new one, so the same bond is sold again at whatever yield the market then wants.

Auction history for 912810SU3.
Auction dateIssuedTypeOfferedAcceptedBid to coverHigh yield
Feb 11, 2021Feb 16, 2021New issue$27.0bn$36.8bn2.18x1.933%
Mar 11, 2021Mar 15, 2021Reopening$24.0bn$25.5bn2.28x2.295%
Apr 13, 2021Apr 15, 2021Reopening$24.0bn$27.7bn2.47x2.320%

The curve this was priced against →

Index levels before September 30, 2026 are back-tested. They were computed after the fact by applying the rules to historical data, which benefits from hindsight in the choice of rules, and an index cannot be invested in directly. Methodology v1.0 takes effect at that rebalance, when levels begin to be struck on the day; the rulebook is identical either way, and the version is published on every row.

A fitted curve is a fit, not a quote. Daily error averages 3.8 basis points across the history and reaches about 20 on the worst days, in December 2008, when the market was genuinely hard to fit one smooth curve to. Every curve page publishes its own fit error rather than burying it.

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Safe Rate™, Safe Rate Indices™ and the Safe Rate US Treasury Index™ are trademarks of Safe Rate, claimed through use in commerce and not registered. Third-party marks are the property of their owners, which are not affiliated with and do not endorse this data.

Curves are fitted from public Treasury data and carry fit error; figures are not a record of trading, and an index cannot be invested in directly. No claim of compliance with the IOSCO Principles for Financial Benchmarks is made or implied. Not investment advice, not an offer, and not a recommendation to buy or sell any security.