Simple Expression: This allows user to perform arithmetic operations. The allowed operators are +, -, *, and / for addition, subtraction, multiplication and division respectively. E.g., Field1 + Field2 gives you sum of existing fields Field1 and Field2.
I have problem the custom reports, especially on the Simple Expression type fields, which allow the user to perform arithmetic operations. In fact, the name of the field I made was very simple, without symbols or special characters
Information that appears "Unable to substitute the expression. Unrecognized field name(s) detected