Cost of capital toolkit

Every discounted valuation needs a rate. Most valuation errors that survive review are rate errors. A rate built in one currency gets applied to cash flows in another. A regression beta describes a period that no longer matches the business. Book weights sit where market weights belong.

The arithmetic is fully scripted. Your job is choosing the inputs — which comparables, which premium estimator, gross or net debt — and defending those choices.

The scripts

Two of them, both pure standard library with nothing to install. Every subcommand takes JSON on stdin (or --in FILE) and prints JSON.

resources/costofcapital.py does the arithmetic.