Format WMI Object's RAW data based on the previous sample.

        Do not override the original WMI Object !

def _format_property_values(self, previous, current):
        """
        Format WMI Object's RAW data based on the previous sample.

        Do not override the original WMI Object !
        """
        formatted_wmi_object = CaseInsensitiveDict()

        for property_name, property_raw_value in iteritems(current):
            counter_type = self._property_counter_types.get(property_name)
            property_formatted_value = property_raw_value

            if counter_type:
                calculator = self._get_property_calculator(counter_type)
                property_formatted_value = calculator(previous, current, property_name)

            formatted_wmi_object[property_name] = property_formatted_value

        return formatted_wmi_object