condition mean min max ZT0-3 6.308702500000001 5.24131 7.376095 ZT4-7 3.379905 3.379905 3.379905 ZT8-11 3.85867 3.85867 3.85867 ZT12-15 0 0 0 ZT16-19 5.5026399999999995 5.5026399999999995 5.5026399999999995 ZT20-23 4.73837 4.73837 4.73837