Overriding Variables

This article explains how to override variables in Model Reef scenarios.

You will learn:

  • How variable overrides work when each scenario is a separate model.

  • Which parts of a variable you typically change by scenario.

  • How to keep overrides traceable and easy to review.

Because each scenario is its own model, overriding variables is simply editing them in that scenario model.

1

Variable copies per scenario

When you duplicate a model to create a scenario:

  • Every variable is copied into the new model.

  • The copy in Scenario A is independent from the copy in Scenario B.

  • Editing a variable in one scenario does not affect any other scenario.

This makes variable overrides straightforward and safe.

2

Common variable overrides between scenarios

Typical differences between scenario models include:

  • Revenue volumes or growth rates.

  • Prices, discounts or take up rates.

  • Staff hiring, headcount and salary levels.

  • Opex efficiency or cost out assumptions.

  • Capex timings and project scope.

  • Tax rate or incentive assumptions.

Any variable field can be changed in a scenario model, including timing, formula and type if needed.

3

How to override a variable in a scenario model

To override a variable for a particular scenario:

  • Open the scenario model (for example Client - FY25 - Upside).

  • Open the Variable Editor for the variable you want to override.

  • Adjust drivers, presets, formulas or timing as needed.

  • Save the changes.

The scenario model recalculates its P&L, Balance Sheet, Cashflow, Cash Waterfall and valuation based on the override.

4

Tracking and documenting overrides

To keep overrides easy to understand later:

  • Use notes on the variable to explain scenario specific logic.

  • Tag key variables with labels such as Scenario override, Upside change or Downside change.

  • Keep naming and category structures consistent across scenarios so matching variables are easy to recognise.

This is essential when many variables differ between scenarios.

5

Minimising unnecessary overrides

Try to avoid overriding variables where:

  • The input should remain the same across all scenarios (for example statutory tax rules in some jurisdictions).

  • The impact is minor compared to major scenario levers.

Fewer, well targeted overrides make it clearer what really drives the difference between scenarios.


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