While representing numerical data with the help of the Symbols representation, it is possible to facilitate the reading adding a color gradation enabling the class representation.
To do so, just link first the Data module to the Symbols module, and then the Data module to the Quantification module. This quantification can then be linked to the Symbols module. In this case, the Symbols representation puts up with two entries. Of course, you can define the parameters of the quantification at will.