condition mean min max ZT0-3 19.329358333333335 9.493125 25.626350000000002 ZT4-7 9.35933 9.35933 9.35933 ZT8-11 7.899875 7.899875 7.899875 ZT12-15 10.72025 10.3758 11.0647 ZT16-19 12.107800000000001 12.107800000000001 12.107800000000001 ZT20-23 23.9251 23.9251 23.9251