Modified Duration of Bonds
Modified duration is the name given to the price sensitivity, and is the percentage change in price for a unit change in yield.
Modified duration depends on a nonlinear combination of coupon frequency, the number of whole coupon periods, the fraction of year until next coupon, annual yield and the annual coupon rate.
Formula
![Copy to Clipboard (QuantityVariable["f", "Unitless"] + QuantityVariable["y", "Unitless"])*QuantityVariable[Subscript["D", "m"], "Unitless"] == (-QuantityVariable["y", "Unitless"]^2 + QuantityVariable["n", "Unitless"]*QuantityVariable["y", "Unitless"]*(QuantityVariable["y", "Unitless"] - QuantityVariable[Subscript["r", "c"], "Unitless"]) - QuantityVariable["f", "Unitless"]*QuantityVariable[Subscript["r", "c"], "Unitless"] + QuantityVariable["f", "Unitless"]*((QuantityVariable["f", "Unitless"] + QuantityVariable["y", "Unitless"])/QuantityVariable["f", "Unitless"])^QuantityVariable["n", "Unitless"]*QuantityVariable[Subscript["r", "c"], "Unitless"] + QuantityVariable["y", "Unitless"]*QuantityVariable["α", "Unitless"]*(QuantityVariable["y", "Unitless"] + (-1 + ((QuantityVariable["f", "Unitless"] + QuantityVariable["y", "Unitless"])/QuantityVariable["f", "Unitless"])^QuantityVariable["n", "Unitless"])*QuantityVariable[Subscript["r", "c"], "Unitless"]))/(QuantityVariable["y", "Unitless"]*(QuantityVariable["y", "Unitless"] + (-1 + ((QuantityVariable["f", "Unitless"] + QuantityVariable["y", "Unitless"])/QuantityVariable["f", "Unitless"])^QuantityVariable["n", "Unitless"])*QuantityVariable[Subscript["r", "c"], "Unitless"]))](https://www.wolframcloud.com/objects/resourcesystem/marketplacestorage/resources/38c/38cc67fe-9560-4589-8177-309bb62750bc/Webpage/FormulaImage.png)
| symbol | description | physical quantity |
|---|---|---|
| f | coupon frequency | "Unitless" |
| y | annual yield | "Unitless" |
| Dm | modified duration | "Unitless" |
| n | number of whole coupon periods | "Unitless" |
| rc | annual coupon rate | "Unitless" |
| α | fraction of year until next coupon | "Unitless" |
Forms
Examples
Get the resource:
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Get the formula:
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Use some values:
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