--- license: apache-2.0 language: - en pretty_name: US Treasury Events (point-in-time, auctions and official curves) size_categories: - 100K13:00 13:02 ``` Two minutes after the close, stated by the Treasury. That is `knowledge_at`, and `knowledge_time_precision` is `minute`. **4 872 results carry a stated release minute**, the first on 7 April 2008. The other **6 236** do not, and say so. Before March 2008 there is no artifact. Those results are dated to the end of the auction day, because the alternative — assuming the result was public at the close — would hand a backtest the number minutes before anyone had it, on every auction for twenty-nine years. ### The curve does not This is the line most Treasury datasets get wrong, so it is worth quoting the Treasury directly. Its [methodology page](https://home.treasury.gov/policy-issues/financing-the-government/interest-rate-statistics/treasury-yield-curve-methodology) says the inputs are > indicative, bid-side market price quotations (not actual transactions) for > the most recently auctioned securities obtained by the Federal Reserve Bank > of New York **at or near 3:30 PM** each trading day and, further down the same page, > Yield curve rates are **usually available** at Treasury's interest rate > website **by 6:00 PM Eastern Time** each trading day, but may be delayed due > to system problems or other issues. Those are two different instants. 3:30 p.m. is what the number measures; 6:00 p.m. is when anyone could read it. So every curve row carries both: | Column | | |---|---| | `market_observation_at` | 15:30 Eastern — what the number describes | | `knowledge_at` | **18:00 Eastern** — when it could be read | | `knowledge_time_precision` | `modeled_conservative` | | `availability_time_basis` | `treasury_usually_available_by_1800_et` | Dating a curve to 3:30 p.m. would hand a backtest two and a half hours of the afternoon it did not have, every trading day for thirty-five years. The gate fails the build if any curve row is knowable before 18:00 Eastern, and `tests/test_quality.py` proves the check by breaking it. ## What is deliberately missing **`wi_yield` and `auction_tail` are null on every row, and the gate fails the build if either is ever populated.** The tail is the auction's high yield minus the when-issued market yield. No official point-in-time when-issued series exists. The daily par yield curve is not one — it is struck from indicative quotations at 3:30 p.m., hours after most auctions close — and subtracting it from the high yield produces a plausible number measuring something else. A column called `auction_tail` that does not contain an auction tail is worse than no column at all. ## A null is not a zero The Treasury did not start publishing all of this at once, and the differences are large enough to change an analysis. | | Begins | |---|---| | auction query | October 1979 | | bidder categories — indirect, direct, primary dealer | **2008** | | the artifact that states the release minute | **April 2008** | | nominal par yield curve | January 1990 | | bill rates | January 2002 | | TIPS real yield curve | January 2003 | Read a 1995 auction expecting an indirect bid share and you get null, because the Treasury did not publish one. It is not zero, and this dataset never turns it into zero. `metadata/field_coverage.parquet` records the first date every numeric field is populated, so a reader can tell "the Treasury had not started publishing this" apart from "nobody bid". Nowhere in this dataset does an absent field become a zero. ## The methodology changed, and the rates are not recomputed The par yield curve is the output of a procedure, and the procedure changed: the **monotone convex** method replaced the **quasi-cubic hermite spline** as of **6 December 2021**, which the Treasury states on its methodology page. A rate from 2015 and a rate from 2022 are therefore not the same kind of number. Neither is recomputed under the other's method — the published values stand as published. `methodology_id` on every nominal curve row says which procedure produced it, and `metadata/yield_curve_methodology.parquet` says what each one was, with the Treasury's own description and the source URL. ## Maturities come and go, and nothing is filled in The 20-year bond returned in May 2020 after seventeen years away. The 4-month bill was added in October 2022. The set of maturities on the curve is not constant, and this dataset stores the curve in long form so that a maturity the Treasury did not publish is an **absent row**, not a null that looks like missing data and invites interpolation. | Maturity | First published | | |---|---|---| | 3M, 6M, 1Y, 2Y, 3Y, 5Y, 7Y, 10Y | 2 January 1990 | the original set | | 20Y | 1 October 1993 | | | **30Y** | 2 January 1990 | **absent 15 Feb 2002 – 9 Feb 2006**, four years | | 1M | 31 July 2001 | | | 2M | 16 October 2018 | | | 4M | 19 October 2022 | | | 1.5M | 18 February 2025 | | The 30-year gap is the one that catches people: 1 455 days with no long bond on the curve, in the middle of a series that otherwise runs unbroken. Here those days simply have no 30-year row. Nothing is interpolated. A curve published without a 20-year point is published here without one. ## Using it ```python import polars as pl pit = pl.read_parquet("data/pit/*.parquet") # The 10-year constant maturity, as it was actually knowable ten = pit.filter(pl.col("entity_id") == "UST_CMT_10Y").select( "event_date", "knowledge_date", "actual", "change" ) # Every 10-year note auction, at the minute its result was released auctions = pit.filter(pl.col("entity_id") == "UST_AUCTION_10Y_BID_TO_COVER") # Everything a strategy could have known at 4pm Eastern on a given day known = pit.filter( pl.col("knowledge_date") <= pl.lit("2026-09-10T20:00:00").str.to_datetime(time_zone="UTC") ) ``` That last filter is the one that matters. Run it against 4:00 p.m. Eastern and the day's auction results are there — they came out at 1:02 p.m. — but the day's yield curve is correctly absent, because it was not on the Treasury's site until six. ## What is in it | Config | Rows | What one row is | |---|---|---| | `pit` | 268 960 | one number becoming public — 1 287 series, plus a Delta table | | `auction_results` | 11 108 | one completed auction, at the minute its result was released | | `auction_calendar` | 11 114 | one auctioned or announced security, dated from its announcement | | `auction_announcements` | 11 114 | one announcement, with its competitive and noncompetitive closing times | | `nominal_yield_curve` | 113 836 | one maturity of one day's par yield curve, 1990→ | | `real_yield_curve` | 34 141 | one maturity of one day's TIPS par real curve, 2003→ | | `bill_rates` | 26 453 | one bill maturity of one day, on both quote conventions | | `curve_features` | 9 180 | derived slopes and one spread, per trading day | Auctions split 7 396 bills, 1 967 notes, 934 cash management bills, 394 bonds, 269 TIPS and 154 floating rate notes. Six are announced but not yet held. `pit` keys auction metrics by **term** rather than by CUSIP, so `UST_AUCTION_10Y_BID_TO_COVER` runs across issues instead of stopping when one bond is auctioned. Curve points are `UST_CMT_10Y`, `UST_REAL_CMT_10Y`, `UST_BILL_13W_CE`; a bill becomes two series because it is quoted two ways. One limitation worth knowing: in 1984-85 the Treasury occasionally auctioned two securities of the same odd term on the same day, and with no artifact to give them different minutes, 12 `pit` rows share an entity, a date and an instant. `record_id` keeps them apart, and the gate reports them rather than hiding them. ## Derived, and labelled as such `curve_features` is arithmetic on two numbers that were public at the same instant, so it inherits that instant. Where a leg is missing — no 20-year point between 2002 and 2020, no real curve before 2003 — the feature is null rather than interpolated. One caution on `nominal_10y_minus_real_10y_bp`: it is a spread between two official curves published for the same day. It is **not** a market breakeven. Both legs are par yields struck from indicative quotations, and neither is a traded inflation instrument. In `auction_results`, `dealer_accepted_pct`, `direct_accepted_pct`, `indirect_accepted_pct`, `noncompetitive_accepted_pct` and `tendered_to_offering` are computed only from numbers in the same result, and are null wherever either side is absent. In `pit` they carry `value_method = "derived"`; everything else is `"reported"`. ## Provenance Every row carries `source_url` and, where an artifact was read, `raw_sha256` — the digest of the exact bytes the Treasury served. Nothing here comes from FRED, a vendor, or a mirror: a secondary copy of a Treasury rate cannot carry the one thing this dataset exists to record. Source: the United States Department of the Treasury, a US Government work in the public domain. The Department does not endorse, certify or verify this dataset. The additions here — the release instants, the long-form curves, the validation — are Apache-2.0. ## Rebuilding it The first build reads 6 229 auction artifacts and 185 rate files, and takes about thirty-five minutes. Every run after that reuses them — a finished auction's result cannot change, and neither can a year of rates that is over — and finishes in **under three seconds**, having asked the Treasury for seven documents: the auction query, the announced list, and the current year of each of the five rate feeds. ```bash python -m recipe.cli build # incremental python -m recipe.cli build --rebuild # read everything again; what a parser change needs ``` The two produce identical tables; `tests/test_auctions.py` covers which rows are eligible for reuse and why a date-precision row is not. ## Related [us-economic-events](https://huggingface.co/datasets/ZipLime/us-economic-events) · [fomc-events](https://huggingface.co/datasets/ZipLime/fomc-events) · [commitments-of-traders](https://huggingface.co/datasets/ZipLime/commitments-of-traders)