condition mean min max ZT0-3 1.5670875 1.367885 1.76629 ZT4-7 1.193703 1.193703 1.193703 ZT8-11 2.4054699999999998 2.4054699999999998 2.4054699999999998 ZT12-15 3.09034625 2.87298 3.3077125 ZT16-19 1.9834433333333332 1.8368066666666667 2.13008 ZT20-23 0 0 0