condition mean min max ZT0-3 17.9379566975 11.999341565 23.87657183 ZT4-7 16.6399888325 12.43855668 20.841420985 ZT8-11 34.533924 28.95222488 40.115623119999995 ZT12-15 23.145193175 15.982673305 30.307713045 ZT16-19 10.12158720875 8.507185832000001 11.7359885855 ZT20-23 8.5242240565 8.4792041535 8.5692439595