# Rate calculation modules

URL: https://municorn.us/build/rate-calculation-modules/
Updated: 2026-09-08
Tags: build, rates

> **Cite as:** Municorn.us, "Rate calculation modules", Municorn water loss index, https://municorn.us/build/rate-calculation-modules/ (source filings retrieved 2026-09-08).
> **Licence:** CC BY 4.0 — https://creativecommons.org/licenses/by/4.0/ — reuse and redistribution are permitted with attribution to Municorn.us and a link to this URL.
> **Caveat that must travel with these figures:** "Water loss" is at least three different quantities depending on the jurisdiction, and nothing here supports a comparison between states.

Cost allocation and rate design as a spreadsheet or a Python module, built against your own class structure and your own cost pools, so the model is yours to run and to defend.

## What it is

The calculation layer of a cost-of-service study, built once against your own method. Cost pools, allocation factors, units of service, and the rate design that recovers the revenue requirement, with every client-specific input on one tab and the calculation tabs referencing only that tab.

It is your method, not ours. We do not have a house allocation and we are not trying to sell you one.

## What you hand us

Your class structure, your cost pools and the allocation factors you already use. If you have a model you like, hand us that: refactoring an existing one so its inputs are separable is usually faster than starting over and always easier to check.

## What you get back

A workbook or a module, with an inputs tab, a documented calculation path from cost pool to rate, and a test that reproduces a study you have already published. That last part matters — a model that cannot reproduce a result you have defended is a model you cannot use.

## What it is built from

Nothing of ours. This is built from your method and your figures. Where the study also needs filed public data — a peer set, a loss figure — that comes from the corpus and carries its own citation.

## What it does not do

It does not decide the allocation. Which costs are demand-related and which are commodity-related is a professional judgment you are paid for, and a module that made it for you would be answering the question you were hired to answer.

It does not produce the study. It is the arithmetic under a study; the narrative, the exhibits and the recommendation are yours.

It is not a product with a license. It is built for one firm's method, and we do not resell it.

_Municorn.us · https://municorn.us/build/rate-calculation-modules/ · CC BY 4.0 https://creativecommons.org/licenses/by/4.0/ · source filings retrieved 2026-09-08_

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