# What-If Analysis

Use `analysis` for Excel's native Goal Seek, scenarios, scenario summaries, and one- or two-variable data tables.

## Goal Seek

The formula cell must contain a formula, and the changing cell must be one of its inputs.

```text
analysis(action="goal-seek", sheetName="Model", formulaCell="B10", goal=10000, changingCell="B3")
```

Goal Seek changes the workbook immediately. Read both cells afterward when the exact final values matter.

## Scenarios

Scenario values must contain exactly one value per cell in `changingCells`, in range order.

```text
analysis(action="create-scenario", sheetName="Model", scenarioName="Growth",
         changingCells="B3:B5", values=[0.08, 1200, 0.35])
analysis(action="show-scenario", sheetName="Model", scenarioName="Growth")
analysis(action="list-scenarios", sheetName="Model")
```

Use `create-scenario-summary` after defining two or more scenarios. Set `reportType` to `summary` for a normal report sheet or `pivot-table` for a Scenario PivotTable. `resultCells` should identify formulas that depend on the changing cells.

## Data Tables

Prepare the worksheet layout first, including the formula in the table's corner and the input values along its first row or column.

- One-variable row table: provide `rowInputCell`.
- One-variable column table: provide `columnInputCell`.
- Two-variable table: provide both.

```text
analysis(action="create-data-table", sheetName="Model", tableRange="A1:B11", columnInputCell="D1")
```

Data tables can be calculation-intensive. Use `calculation_mode` when controlling recalculation around larger workbook edits.

## Solver Is Not Exposed

Solver is an optional VBA add-in, not an Excel PIA API. Microsoft requires users to enable the add-in in Excel Options and establish a VBA reference before calling Solver functions. Do not try to invoke Solver through `vba`, enable the add-in, or change macro-security settings automatically. Use Goal Seek for one-variable targets or document that multi-variable constrained optimization requires user-configured Solver.