condition mean min max ZT0-3 7.8500000000000005 7.8500000000000005 7.8500000000000005 ZT4-7 2.2 2.2 2.2 ZT8-11 5.35 5.35 5.35 ZT12-15 19.75 19.75 19.75 ZT16-19 6.800000000000001 6.800000000000001 6.800000000000001 ZT20-23 3.3499999999999996 3.3499999999999996 3.3499999999999996