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Treasury indices
Eleven total-return indices of the U.S. Treasury market, valued every business day and rebalanced at each month-end. They are constructed by Safe Rate from public Treasury data, not official U.S. Treasury statistics.
The indices
| Code | Index | Covers | Ticker |
|---|---|---|---|
| broad | US Treasury | Nominal notes and bonds, one year and over | SR-UST-TR |
| 0103 | 1-3 Year | 1 to 3 years | SR-UST-TR-0103 |
| 0307 | 3-7 Year | 3 to 7 years | SR-UST-TR-0307 |
| 0710 | 7-10 Year | 7 to 10 years | SR-UST-TR-0710 |
| 1020 | 10-20 Year | 10 to 20 years | SR-UST-TR-1020 |
| 20PL | 20+ Year | 20 years and over | SR-UST-TR-20PL |
| BILL | 1-3 Month Bill | 1 to 3 month bills | SR-UST-TR-BILLformerly SR-UST-BILL |
| SHRT | 1-12 Month | 1 to 12 months, bills and aged coupons together | SR-UST-TR-SHRTformerly SR-UST-SHRT |
| TIPS | Inflation-Linked | Inflation-linked, one year and over | SR-UST-TR-TIPSformerly SR-UST-TIPS |
| AGG | US Treasury Aggregate | The whole marketable market: bills, coupons, linkers and floaters | SR-UST-TR-AGGformerly SR-UST-AGG |
| FRN | Floating Rate | Floating rate notes | SR-UST-TR-FRNformerly SR-UST-FRN |
Reading the numbers
A level is a total return, not a yield. It grows with coupon income and moves inversely with yields, so a rising level usually means yields fell. Compare levels as returns: the change from one level to another is the return over that span.
Latest versus month-end. latest is the most recent business day and can be is_provisional while that day's prices may still be revised. last_month_end is the last completed month, which is final. Use month-ends for performance reporting.
Units. Returns, weights, yields and coupon rates are in percent. Convexity follows the published-index convention, the textbook quantity divided by 100, so half of it approximates the price change in percent for a one-point yield move.
Dates: two conventions to know
The portfolio is struck at each month-end and held for the following month. Two kinds of data describe the same period from opposite ends:
- Analytics carry
rebalance_date, the period start. Analytics with rebalance_date 2026-08-31 describe the portfolio struck on 31 August and held through September. - Completed-period constituents are addressed by the period end.
/constituents/2026-08-31is the portfolio struck at the end of July and held through August, with each security's August return.
The current month is /constituents with no date: the portfolio struck at the last rebalance, with returns running to as_of_date.
Endpoints
| GET /v1/indices | Every index: latest daily level and last month-end |
| GET /v1/indices?date=YYYY-MM-DD | Every index's daily level on one day |
| GET /v1/indices/{code} | One index |
| GET /v1/indices/{code}/levels?from=&to= | Daily total-return history |
| GET /v1/indices/{code}/returns | Month-, quarter- and year-to-date |
| GET /v1/indices/{code}/analytics | Yield, duration, convexity, key rates |
| GET /v1/indices/{code}/constituents | Current (open-period) holdings |
| GET /v1/indices/{code}/constituents/{date} | A completed month's holdings |
curl "https://api.saferate.markets/v1/indices/broad/levels?from=2026-01-01" \ -H "Authorization: Bearer $SAFERATE_MARKETS_KEY"
Every field, type and error is in the generated reference at https://api.saferate.markets/reference. Over MCP, the same data is the get_treasury_index tool.
Methodology and licensing
The construction rules, the published history and the per-index pages are on saferate.com/treasury/indices. Using an index in your own analysis or client reporting is covered by your plan. Using one inside a financial product, as a fund benchmark or in a product whose payout references a level, needs a benchmark licence.