# Penetration maps

You can use penetration maps to see how a specific group of customers spreads across a map, compared to the overall customer base.

> [!NOTE]
>
> **Explainer: Penetration maps**
>
> In this example:
>
> - The analysis group consists of people who've booked a holiday to Sweden.
> - The base includes everyone in your system.
>
> The penetration map shows the concentration of Sweden holidaymakers in each area relative to the base group.
>
> This insight helps marketers focus resources on areas with the highest density of target customers.
>
> Penetration maps help you make data-driven decisions to optimise your marketing strategies.

To create a penetration map:

1. Complete the following steps to create [Workbook maps](<https://help.apteco.com/en/orbit/audiences/audience-workbooks/audience-workbook-maps/workbook-maps/index.md>).
2. Now, add a filter to your audience. For example, people who have picked Sweden as a booking destination.
3. Select **Apply**.
4. Select your penetration map.
5. Select **Colour Scale** and change the Shading type from Quantiles to **Index Shading**.
6. Change the **Equal ranges** to your preferred unit either side of your index.
7. Adjust your **Low value** and **High value** as required.

   You've now created your penetration map.

   You have an analysis group and a base group. You can see how customers who've booked holidays to Sweden spread across the map, compared to the general population.