condition mean min max ZT0-3 21.502725 19.889400000000002 23.11605 ZT4-7 20.3489 20.3489 20.3489 ZT8-11 24.20485 24.20485 24.20485 ZT12-15 0 0 0 ZT16-19 29.083399999999997 29.083399999999997 29.083399999999997 ZT20-23 23.476950000000002 23.476950000000002 23.476950000000002