To suppress the display of fields with value zero, set their Format property to #. The pound sign is a formatting symbol that displays only significant digits (no leading or trailing zeros).
To force the display of a certain number of digits, use a format like "0000". The zero forces the display of a digit, including leading and trailing zeros.
Each format string can have up to three sections separated by semi-colons. If two sections are provided, the first is used for positive values and zero, the second for negative values. If three sections are provided, the first is used for positive values, the second for negative values, and the third for zero. For example: "#;(#);ZERO".