**What is a document formula?**

A document formula is a value calculated for the document. This value will be available as a variable in your document and will enable you to create : filters, calculation fields or other document formulas. Document formulas are calculated automatically in real time from the variable you used to define it.

Available variables to create document formulas are :

- Results from other document formulas
- Values of numeric, duration or calculated fields on your post-its (for the document formulas, you need to choose from the functions : average and sum of the field values of every post-its in the document)

**Create a document formula**

Start by clicking on the "formulas" icon **(1)** in the toolbar.

If you just started using formulas, this tab is probably empty. For each line you can find : the formula's name, its definition and Its calculated value.

Here for exemple, the formula "Takt time" (2) is composed of the variables "Temps d'ouverture" and "Besoin client", defined above, and the result of the calculation is 420.

In order to create a formula, click on "New formula" **(3)**.

**(4) **Type a name for you formula.

**(5)** Define your formula : you can use numeric values, basic operators (+, -, /, *, (, ) ) and variables from your document.

To call a variable, use the @ key of your keyboard and choose the variable in the list.

For a variable from another document formula, you can directly use the value.

For a variable from a post-it field, you can choose between the average and sum functions (of the field values of each post-its of the document)

Finally, for he duration fields, you can also choose the time unit to use in the formula (for exemple : you typed 2 days in average within the values of field "A" and you specified a variable "Moy(A)" in hours, then the value used for calculation will be 48 (2 days * 24 hours)).

**(6)** Once you have defined your formula, click on **"Validate"**.

**Edit or delete an existing formula.**

To edit or delete a document formula, click on the "menu" icon next to the formula and select the wanted option.

### Display formula's result within your document.

You can drag and drop a formula from the "Document formulas" tab to add the formula's result to your document.