ADDING THREE SUM FIELDS (THREE COLUMNS)

Hello and I'm making progress with CR.  I'm working on using the sum function for three columns, this is my setup.the three columns representing bills each column for a different company. I have used the summary function (min) for a total in the report footer, having problem with the sum function to add all three summary functions together. this is the code that's in the formula workshop. the Form workshop sees no problem with the function,, when inserting the field in the footer I only get 0

CURRENCYVAR_DEBT;

//SUM({_DEBT.CCBAL1}+{_DEBT.CCBAL2}+{_DEBT.CCBAL3});

Any help would be appreciated and have a good evening