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. For an inflation-linked security the difference is mostly inflation rather than float: Treasury reports what a holder is owed today, which includes the uplift shown as the index ratio above, while the index keeps original par and carries the uplift in the price. The index figures are published per holding.
Inflation-linked measures, September 30, 2026
An inflation-linked security prices off a real curve, so its yield is a real yield, a return above inflation rather than in cash terms, and its principal is indexed. The figures below are in REAL terms unless labeled otherwise.
Real yield
3.371%
Index ratio
1.0880
Real duration
19.455 yr
DV01
0.1520
Convexity
4.75
Real clean price
77.844
Accrued (real)
0.271
Real dirty price
78.115
Indexed principal
108.802
Money clean price
84.696
The index ratio is a multiplier, not a percentage: 1.0880 means the principal is worth that many times its original face today. So the real clean price of 77.844 is not what a buyer pays , multiply by the ratio to get 84.696 per 100 of original face.
Against the fitted real curve
Priced 1.1 bp cheap to the real curve on that day, 17.16 cents per 100 of face.
That is -0.49 standard deviations from its own typical residual.
Real yield, 649 observations
Price history
649 trading days to Sep 30, 2026
The most recent 20 trading days of prices for 912810TY4.
Date
Bid
Offer
Close
Sep 30, 2026
78.063
78.000
77.844
Sep 29, 2026
78.109
78.063
78.438
Sep 28, 2026
78.563
78.500
78.563
Sep 25, 2026
79.219
79.156
79.500
Sep 24, 2026
80.094
80.031
79.656
Sep 23, 2026
81.234
81.188
80.906
Sep 22, 2026
82.422
82.375
82.438
Sep 21, 2026
82.453
82.375
82.719
Sep 18, 2026
81.797
81.750
81.656
Sep 17, 2026
82.125
82.063
82.375
Sep 16, 2026
82.281
82.219
81.656
Sep 15, 2026
81.906
81.844
81.875
Sep 14, 2026
82.375
82.313
82.219
Sep 11, 2026
82.469
82.406
82.031
Sep 10, 2026
82.656
82.594
82.188
Sep 9, 2026
83.172
83.094
83.375
Sep 8, 2026
83.906
83.844
83.750
Sep 4, 2026
83.688
83.625
83.750
Sep 3, 2026
84.109
84.063
83.688
Sep 2, 2026
83.484
83.438
83.438
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.
2 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.
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.