super( min, max, dt );
}
//return the difference in YearMonths
public int count(Object start, Object end) {
BigDateTimeValueType calendarStart = ((IDateTimeValueType)start).getBigValue();
BigDateTimeValueType calendarEnd = ((IDateTimeValueType)end).getBigValue();
// possible overflow error
int numYears = calendarEnd.getYear().intValue() - calendarStart.getYear().intValue() + 1;
int numMonths = calendarEnd.getMonth().intValue() - calendarStart.getMonth().intValue() + 1;
return 12 * numYears + numMonths;
}