condition mean min max ZT0-3 7.4794599999999996 7.4794599999999996 7.4794599999999996 ZT4-7 8.923295 8.923295 8.923295 ZT8-11 4.786595 4.786595 4.786595 ZT12-15 3.56591 3.56591 3.56591 ZT16-19 3.26788 3.26788 3.26788 ZT20-23 6.21297 6.21297 6.21297