# Treasury Ladder

Source: https://www.yieldcurve.pro/treasury-ladder

Build a **Treasury bond ladder** using current US Treasury par curve yields.
Specify portfolio size, number of rungs, maturity range, and an
optional reinvestment rate to see per-rung metrics and aggregated
cash flows.



### Inputs

* **Portfolio Size** ($) — total amount to invest across all rungs
* **Number of Rungs** — how many bonds in the ladder (2–20)
* **Min Maturity** / **Max Maturity** — shortest and longest rung
* **Reinvestment Rate** (%) — assumed flat rate for reinvesting coupons and maturing principal
* click **GO** to compute

### Charts

* **Par Curve with Rungs** — the interpolated par curve with each rung marked
* **Cash Flow Schedule** — stacked bar chart of semiannual coupon and principal flows

### Results

* **Summary card** — portfolio-level aggregates: WAM, Avg Yield, Modified Duration, DV01, Convexity, Annual Income, Annualized Return
* **Ladder table** — one row per rung with the following columns:
    * **Rung** — sequence number (1 through N)
    * **Maturity** — time to maturity, linearly spaced from min to max and rounded to the nearest month
    * **Coupon (%)** — par yield at that maturity, interpolated from the live curve
    * **Face Value** — equal dollar allocation (portfolio size / number of rungs)
    * **Annual Income** — face value multiplied by coupon rate
    * **Duration** — modified duration of the rung (par bond, semiannual compounding)
* **Cash flow table** — semiannual period-by-period breakdown of all coupon and principal payments aggregated across rungs (collapsible)

### Use Cases

* construct a maturity-diversified Treasury portfolio with predictable cash flows
* compare income and duration across different ladder configurations
* estimate total return under a static reinvestment assumption
* understand how rung spacing affects portfolio WAM and interest rate risk

### Assumptions

* all bonds purchased at par (coupon rate = par yield)
* semiannual coupon payments per US Treasury convention
* reinvestment model is static — coupons and principal compound at the
  flat reinvestment rate, not reinvested into new ladder rungs
* yields interpolated via PCHIP from the live par curve

Per-ladder pages (e.g. `/treasury-ladder/10-year`) show pre-computed
results for common ladder configurations at current yields.