# US Treasury Yield Indices

### US 3M TBill Yield Index (US3M‑USDYP)

**What it is:** a perp that tracks the annualized **3‑month U.S. Treasury Bill yield**, enabling directional rates trading and rate hedging in perp form.

<table><thead><tr><th width="202.3828125">Key Parameters</th><th width="377.6171875">Details</th></tr></thead><tbody><tr><td>Collateral</td><td>USDYP</td></tr><tr><td>Initial Oracle Price</td><td>3.500</td></tr><tr><td>Open Interest Cap</td><td>$10,000,000</td></tr><tr><td>Funding Multiplier</td><td>1</td></tr></tbody></table>

### Oracle & marking

* **Open (9:30–16:00 ET):** 100% weight to the Pyth US3M rate feed
* **Off‑hours:** a conservative blend anchored to the last known yield, with a small nowcast component

This approach is designed to avoid erratic off‑hours moves while still allowing minor proxy‑driven adjustments.

### Funding setup&#x20;

Configured with a fixed‑leg component:

* `setFundingInterestRates: -0.00046 per 8hr` (≈ 5% APY magnitude)

Mechanically (in economic terms):

* **Longs receive a “risk‑free” streaming leg** representative of the index,
* **Shorts pay the leg** and benefit if short‑rates fall below the fixed component.

> Note: sign conventions are engine‑specific. The important property is the **fixed leg magnitude** and which side receives/pays it.

### Strategies

* **Go long:** earn short‑rate exposure without holding bills; express “rates up”.
* **Go short:** hedge rate‑sensitive portfolios; express “rates down”.

### Notes & risks

Rates can gap around macro events. Off‑hours logic reduces noise, not risk.

[See additional market mechanics and parameters](https://docs.nunchi.trade/market-mechanics-and-parameters#t-bill-market-parameters)