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YIELD CURVE

Butterfly Spread

Measures relative curvature around a middle maturity.

Formula

Butterfly = 2×Middle yield - Short yield - Long yield

Variables: Short, middle and long maturity yields

What it means

Measures relative curvature around a middle maturity.

Example

For a 2s5s10s butterfly, combine the 2Y, 5Y and 10Y yields using the stated weights.

How to interpret it

This concept should be read together with its market convention, measurement horizon and underlying instrument. BondStats presents it as an analytical reference rather than investment advice; instrument documentation and primary market rules remain authoritative.

BondStats reference content is independently written. Mathematical relationships, abbreviations and market conventions are presented for educational and analytical use.