condition mean min max ZT0-3 2.8499999999999996 2.8499999999999996 2.8499999999999996 ZT4-7 1.4 1.4 1.4 ZT8-11 16.099999999999998 16.099999999999998 16.099999999999998 ZT12-15 3.3499999999999996 3.3499999999999996 3.3499999999999996 ZT16-19 3.05 3.05 3.05 ZT20-23 2.7 2.7 2.7