condition mean min max ZT0-3 1.9500000000000002 1.9500000000000002 1.9500000000000002 ZT4-7 1.5 1.5 1.5 ZT8-11 15.8 15.8 15.8 ZT12-15 1.75 1.75 1.75 ZT16-19 5.3999999999999995 5.3999999999999995 5.3999999999999995 ZT20-23 3.8499999999999996 3.8499999999999996 3.8499999999999996