Power BI conditional formatting range

Hi,

In conditional formatting used within tables and maps user can select a colour associated with minimum and maximum value that is displayed within that visual. Power BI then automatically selects the appropriate intermediate colour that represents the intermediate values within that table or map. 

My question is whether this intermediate value/colour selection is based on a standard range/criteria within the data such as a quartile or decile or centile or similar? Grateful if someon could provide a response.

Thanks.