Financial model end to end: calculation and deck
Turnover in, a finished financial-model deck out — with arithmetic you can verify on paper.
- The client deck is generated rather than laid out by hand before every meeting
- The numbers are reproducible: the same input always yields the same result
- The file opens in both PowerPoint and Google Slides
The problem
Client financial models were computed in a spreadsheet and moved into a deck by hand. That is slow, but the worse part is that every manual assembly is a chance for a figure from a previous version to reach a slide — and you get to defend it in the meeting.
How it works
The calculation moved into code and is **deliberately AI-free**: a financial model must be deterministic and explainable step by step, or it cannot be defended in front of a client. A layer for personalising constants is allowed for by the architecture but plugs in separately and does not affect the reproducibility of the core calculation. The output is a deck compatible with both editors.
The hard part
The temptation to drop a language model in here was direct — 'let it pick industry coefficients'. Declining was deliberate: in a financial model the value is not plausibility but that every number can be derived on paper while the client watches. Room for personalisation was left, but outside the deterministic core.
Evidence
- The calculation is fully deterministic: no AI in the loop
- Sample inputs and outputs live in the repository — the model is checkable
- The build is containerised: identical results on any machine