By minimising the KPIs you decrease their size. In order to minimise the KPIs, you must first have maximised them. If you have not done that, you can disregard the information in this section.
To minimise the KPIs:
Go to the KPIs (see image below).
Click "Minimise" (see the first image below). When you do so, the KPIs will be minimised, meaning they will regain their original size (see the second image below). The original size depends on whether you are showing both the map and the KPIs, or only the KPIs.
