Difference between two times rounded to two decimal places
Example:
hours-from-duration((xs:time(../OPERATION_TIME_SHEET_END_TIME) - xs:time(../OPERATION_TIME_SHEET_START_TIME))) + round(((minutes-from-duration((xs:time(../OPERATION_TIME_SHEET_END_TIME) - xs:time(../OPERATION_TIME_SHEET_START_TIME))) * 100 div 60) div 100) * 100) div 100