condition mean min max ZT0-3 19.44965 19.44965 19.44965 ZT4-7 20.246450000000003 20.246450000000003 20.246450000000003 ZT8-11 14.49145 14.49145 14.49145 ZT12-15 13.090900000000001 13.090900000000001 13.090900000000001 ZT16-19 19.2728 19.2728 19.2728 ZT20-23 18.477200000000003 18.477200000000003 18.477200000000003