condition mean min max ZT0-3 17.7129 17.7129 17.7129 ZT4-7 9.53553 9.53553 9.53553 ZT8-11 15.3978 15.3978 15.3978 ZT12-15 17.070999999999998 17.070999999999998 17.070999999999998 ZT16-19 21.6646 21.6646 21.6646 ZT20-23 23.50155 23.50155 23.50155