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, October 20, 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
3.199%
Index ratio
1.0903
Real duration
19.566 yr
DV01
0.1583
Convexity
4.79
Real clean price
80.531
Accrued (real)
0.387
Real dirty price
80.918
Indexed principal
109.025
Money clean price
87.800
The index ratio is a multiplier, not a percentage: 1.0903 means the principal is worth that many times its original face today. So the real clean price of 80.531 is not what a buyer pays , multiply by the ratio to get 87.800 per 100 of original face.
Against the fitted real curve
Priced 1.6 bp cheap to the real curve on that day, 25.07 cents per 100 of face.
That is 0.26 standard deviations from its own typical residual.
Real yield, 662 observations
Price history
662 trading days to Oct 20, 2026
The most recent 20 trading days of prices for 912810TY4.
Date
Bid
Offer
Close
Oct 20, 2026
80.438
80.375
80.531
Oct 19, 2026
80.063
80.000
79.625
Oct 16, 2026
80.734
80.656
80.531
Oct 15, 2026
80.406
80.313
80.188
Oct 14, 2026
78.672
78.594
79.188
Oct 13, 2026
78.672
78.594
78.563
Oct 9, 2026
78.000
77.938
77.906
Oct 8, 2026
77.563
77.500
78.063
Oct 7, 2026
76.969
76.906
77.250
Oct 6, 2026
77.656
77.594
77.500
Oct 5, 2026
77.188
77.125
77.125
Oct 2, 2026
77.891
77.813
77.625
Oct 1, 2026
77.984
77.938
78.000
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
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.