condition mean min max ZT0-3 20.7512011575 18.724071435 22.77833088 ZT4-7 12.787226165 11.211557965 14.362894364999999 ZT8-11 17.915526275 14.897373690000002 20.93367886 ZT12-15 13.625577790249999 11.7572970655 15.493858515 ZT16-19 7.940863930500001 7.406820532 8.474907329 ZT20-23 10.2704874055 10.143740975 10.397233836000002