condition mean min max ZT0-3 22.299116666666666 21.52845 23.1724 ZT4-7 27.6929 27.6929 27.6929 ZT8-11 17.56795 17.56795 17.56795 ZT12-15 26.640925000000003 20.52925 32.7526 ZT16-19 30.1986 30.1986 30.1986 ZT20-23 31.325200000000002 31.325200000000002 31.325200000000002