condition mean min max ZT0-3 14.767982 14.767982 14.767982 ZT4-7 11.292871 11.292871 11.292871 ZT8-11 11.816607999999999 11.816607999999999 11.816607999999999 ZT12-15 11.385966 11.385966 11.385966 ZT16-19 9.717996 9.717996 9.717996 ZT20-23 9.954901 9.954901 9.954901