condition mean min max ZT0-3 2.5396574999999997 2.4919399999999996 2.5873749999999998 ZT4-7 2.46224 2.46224 2.46224 ZT8-11 2.3687500000000004 2.3687500000000004 2.3687500000000004 ZT12-15 0 0 0 ZT16-19 3.393205 3.393205 3.393205 ZT20-23 2.1805399999999997 2.1805399999999997 2.1805399999999997