3-statement-model

## Environment

This skill assumes **headless openpyxl** — you are producing an .xlsx file on disk.
Follow the `excel-author` skill's conventions for cell coloring, formulas, named ranges, and sensitivity tables.
Recalculate before delivery: `python /path/to/excel-author/scripts/recalc.py ./out/model.xlsx`.

# 3-Statement Financial Model Template Completion

Complete and populate integrated financial model templates with proper linkages between Income Statement, Balance Sheet, and Cash Flow Statement.

## ⚠️ CRITICAL PRINCIPLES — Read Before Populating Any Template

**Formulas over hardcodes (non-negotiable):**
- Every projection cell, roll-forward, linkage, and subtotal MUST be an Excel formula — never a pre-computed value
- When using Python/openpyxl: write formula strings (`ws["D15"] = "=D14*(1+Assumptions!$B$5)"`), NOT computed results (`ws["D15"] = 12500`)
- The ONLY cells that should contain hardcoded numbers are: (1) historical actuals, (2) assumption drivers in the Assumptions tab
- If you find yourself computing a value in Python and writing the result to a cell — STOP. Write the formula instead.
- Why: the model must flex when scenarios toggle or assumptions change. Hardcodes break every downstream integrity check silently.

**Verify step-by-step with the user:**
1. **After mapping the template** → show the user which tabs/sections you've identified and confirm before touching any cells
2. **After populating historicals** → show the user the historical block and confirm values/periods match source data
3. **After building IS projections** → run the subtotal checks, show the user the projected IS, confirm before moving to BS
4. **After building BS** → show the user the balance check (Assets = L+E) for every period, confirm before moving to CF
5. **After building CF** → show the user the cash tie-out (CF ending cash = BS cash), confirm before finalizing
6. **Do NOT populate the entire model end-to-end and present it complete** — break at each statement, show the work, catch errors early

## Formatting — Professional Blue/Grey Palette (Default unless template/user specifies otherwise)

**Keep colors minimal.** Use only blues and greys for cell fills. Do NOT introduce greens, yellows, oranges, or multiple accent colors — a clean model uses restraint.

| Element | Fill | Font |
|---|---|---|
| Section headers (IS / BS / CF titles) | Dark blue `#1F4E79` | White bold |
| Column headers (FY2024A, FY2025E, etc.) | Light blue `#D9E1F2` | Black bold |
| Input cells (historicals, assumption drivers) | Light grey `#F2F2F2` or white | Blue `#0000FF` |
| Formula cells | White | Black |
| Cross-tab links | White | Green `#008000` |
| Check rows / key totals | Medium blue `#BDD7EE` | Black bold |

**That's 3 blues + 1 grey + white.** If the template has its own color scheme, follow the template instead.

Font color signals *what* a cell is (input/formula/link). Fill color signals *where* you are (header/data/check).

## Model Structure

### Identifying Template Tab Organization

Templates vary in their tab naming conventions and organization. Before populating, review all tabs to understand the template's structure. Below are common tab names and their typical contents:

| Common Tab Names | Contents to Look For |
|------------------|----------------------|
| IS, P&L, Income Statement | Income Statement |
| BS, Balance Sheet | Balance Sheet |
| CF, CFS, Cash Flow | Cash Flow Statement |
| WC, Working Capital | Working Capital Schedule |
| DA, D&A, Depreciation, PP&E | Depreciation & Amortization Schedule |
| Debt, Debt Schedule | Debt Schedule |
| NOL, Tax, DTA | Net Operating Loss Schedule |
| Assumptions, Inputs, Drivers | Driver assumptions and inputs |
| Checks, Audit, Validation | Error-checking dashboard |

**Template Review Checklist**
- Identify which tabs exist in the template (not all templates include every schedule)
- Note any template-specific tabs not listed above
- Understand tab dependencies (e.g., which schedules feed into the main statements)
- Locate input cells vs. formula cells on each tab

### Understanding Template Structure

Before populating a template, familiarize yourself with its existing layout to ensure data is entered in the correct locations and formulas remain intact.

**Identifying Row Structure**
- Locate the model title at top of each tab
- Identify section headers and their visual separation
- Find the units row indicating $ millions, %, x, etc.
- Note column headers distinguishing Actuals vs. Estimates periods
- Confirm period labels (e.g., FY2024A, FY2025E)
- Identify input cells vs. formula cells (typically distinguished by font color)

**Identifying Column Structure**
- Confirm line item labels in leftmost column
- Verify historical years precede projection years
- Note the visual border separating historical from projected periods
- Check for consistent column order across all tabs

**Working with Named Ranges**
Templates often use named ranges for key inputs and outputs. Before entering data:
- Review existing named ranges in the template (Formulas → Name Manager in Excel)
- Common named ranges include: Revenue growth rates, cost percentages, key outputs (Net Income, EBITDA, Total Debt, Cash), scenario selector cell
- Ensure inputs are entered in cells that feed into these named ranges

### Projection Period
- Templates typically project 5 years forward from last historical year
- Verify historical (A) vs. projected (E) columns are clearly separated
- Confirm columns use fiscal year notation (e.g., FY2024A, FY2025E)

## Margin Analysis

**Note: The following margin analysis should only be performed if prompted by the user or if the template explicitly requires it. If no prompt is given, skip this section.**

Calculate and display profitability margins on the Income Statement (IS) tab to track operational efficiency and enable peer comparison.

### Core Margins to Include

| Margin | Formula | What It Measures |
|--------|---------|------------------|