Project Variables
Project variables let you define shared values once and reuse them across models and scenarios. They help keep models consistent, flexible, and easy to update as assumptions change.
When to use it
When the same value is used in many places across a model
When key assumptions may change over time
When scenarios need to adjust assumptions quickly
How it works
Project variables act as central placeholders for values.
They can be:
Defined at the project level
Used inside node calculations
Overwritten per scenario when needed
Some variables are system-defined (such as project horizon or current period), while others can be custom variables created by users. Variables can hold numeric or non-numeric values.
Using variables ensures that changing a value in one place automatically updates all calculations that rely on it.
Setup
Project variables are defined in the project settings.
Once created, they are available throughout the project and can be referenced in models and scenarios with the $ character preceding the variable name.
Using the feature
Use project variables instead of fixed values in node formulas.
Update assumptions centrally instead of editing multiple nodes.
Override variable values in scenarios to simulate alternatives.
Pin scenario variables to keep them fixed even if project defaults change.
Limitations & edge cases
Variable names must follow naming rules to be usable in formulas.
System-defined variables are managed through project settings, not directly edited everywhere.
FAQ
Why should I use project variables instead of fixed values?
They make models easier to maintain by centralizing key assumptions.
Can variables be different per scenario?
Yes. Variables can be overwritten at the scenario level.
What happens if a project variable changes?
All calculations using that variable update automatically, unless a scenario has pinned its own value.
Are all variables visible in the same place?
Custom variables are listed in the variable overview. Some system variables are configured via project settings.
➡️ See the Project Variables section in the FAQs for more questions.