# ROI model

Use the CSV next to this page or the online calculator (/tools/roi). Every input is yours; the sheet applies the formulas below and nothing else.

| Input | Value | Unit |
| --- | --- | --- |
| Purchase orders per year | | count |
| Minutes of manual work per PO today | | min |
| Share of that work removed | | 0..1 |
| Invoices per year | | count |
| Minutes of manual work per invoice today | | min |
| Share of that work removed | | 0..1 |
| Fully loaded cost per hour | | currency |
| Addressable spend per year | | currency |
| Share outside contracts (maverick) | | 0..1 |
| Price premium on maverick spend | | 0..1 |
| Share of maverick spend brought under contract | | 0..1 |
| Annual software cost | | currency |
| One-off cost | | currency |

Formulas: hours saved = count x minutes / 60 x share removed; time saving = hours x cost per hour; maverick saving = spend x share x premium x share brought under contract; net annual = savings - annual cost; payback months = one-off / net annual x 12.