condition mean min max ZT0-3 4.90463 4.90463 4.90463 ZT4-7 3.77406 3.77406 3.77406 ZT8-11 1.96175 1.96175 1.96175 ZT12-15 1.1846299999999998 1.1846299999999998 1.1846299999999998 ZT16-19 2.70932 2.70932 2.70932 ZT20-23 3.3654 3.3654 3.3654