condition mean min max ZT0-3 0.8560051666666667 0.6368275 0.9816400000000001 ZT4-7 1.18638 1.18638 1.18638 ZT8-11 1.576895 1.576895 1.576895 ZT12-15 3.1748624999999997 2.4179399999999998 3.9317849999999996 ZT16-19 2.3679449999999997 2.3679449999999997 2.3679449999999997 ZT20-23 1.573995 1.573995 1.573995