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
3.373%
Index ratio
1.3270
Real duration
18.957 yr
DV01
0.1196
Convexity
4.06
Real clean price
62.938
Accrued (real)
0.128
Real dirty price
63.065
Indexed principal
132.699
Money clean price
83.517
The index ratio is a multiplier, not a percentage: 1.3270 means the principal is worth that many times its original face today. So the real clean price of 62.938 is not what a buyer pays , multiply by the ratio to get 83.517 per 100 of original face.
Against the fitted real curve
Priced 1.1 bp rich to the real curve on that day, 13.19 cents per 100 of face.
That is -1.72 standard deviations from its own typical residual.
Real yield, 1,901 observations
Price history
1,901 trading days to Sep 30, 2026
The most recent 20 trading days of prices for 912810SG4.
Date
Bid
Offer
Close
Sep 30, 2026
63.125
63.063
62.938
Sep 29, 2026
63.188
63.125
63.375
Sep 28, 2026
63.531
63.469
63.531
Sep 25, 2026
64.094
64.031
64.281
Sep 24, 2026
64.844
64.781
64.469
Sep 23, 2026
65.781
65.719
65.438
Sep 22, 2026
66.766
66.719
66.719
Sep 21, 2026
66.766
66.688
66.969
Sep 18, 2026
66.281
66.219
66.094
Sep 17, 2026
66.563
66.500
66.719
Sep 16, 2026
66.688
66.625
66.156
Sep 15, 2026
66.344
66.281
66.313
Sep 14, 2026
66.750
66.688
66.594
Sep 11, 2026
66.844
66.781
66.438
Sep 10, 2026
67.000
66.938
66.594
Sep 9, 2026
67.391
67.313
67.531
Sep 8, 2026
67.953
67.875
67.813
Sep 4, 2026
67.766
67.688
67.750
Sep 3, 2026
68.063
68.000
67.750
Sep 2, 2026
67.531
67.469
67.500
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.
Free to benchmark against. Paid only to track. Measuring anything against these curves and indices is free. No license, no fee, no registration, and no permission needed to say that you did, including in a prospectus. A fee applies to one thing: launching a product that tracks an index.
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.