condition mean min max ZT0-3 8.92018 8.92018 8.92018 ZT4-7 7.068845 7.068845 7.068845 ZT8-11 7.961245 7.961245 7.961245 ZT12-15 9.139795 9.139795 9.139795 ZT16-19 13.2532 13.2532 13.2532 ZT20-23 10.963799999999999 10.963799999999999 10.963799999999999