condition mean min max ZT0-3 17.8575 17.8575 17.8575 ZT4-7 20.040300000000002 20.040300000000002 20.040300000000002 ZT8-11 14.679549999999999 14.679549999999999 14.679549999999999 ZT12-15 15.2669 15.2669 15.2669 ZT16-19 15.05965 15.05965 15.05965 ZT20-23 17.31605 17.31605 17.31605