A parameter is a property of the legislation that changes over time.

Unlike a variable, a parameter is not specific to a specific entity (person, household…).

For instance:

  • the amount of the minimum wage;

  • the amount of family allowance per children;

  • the marginal tax scale used to calculate the income tax;

  • the maximum age at which a person is entitled to some benefits;

  • the list of regions in which a tax is applicable…

Parameters are used in formulas to calculate variable values.

Read more about their implementation in OpenFisca.