condition mean min max ZT0-3 20.602249999999998 15.557 26.33655 ZT4-7 19.012349999999998 19.012349999999998 19.012349999999998 ZT8-11 19.7695 19.7695 19.7695 ZT12-15 31.344425 26.767 35.92185 ZT16-19 24.62355 24.62355 24.62355 ZT20-23 27.6605 27.6605 27.6605