Why is the sum symbol doesn't appeare at the sidebar?

[I365SvcUsr]

Hi to everyone,

I've setting the column "Importo" as a decimal number and the default summarization as "Sum", but I can't put this column into the matrix's value section (it is valid only for the column and row section) and the sum symbol doesn't appeare at the sidebar

 

This appen with all columns of this data set.

Someone can help me to solved this problem?

Thanks a lot,

ER

[Len_Barr]

Hard to tell without seeing an example of your data - possible that some of the data is in 'string' type and not a number type?