condition mean min max ZT0-3 221.267509 221.267509 221.267509 ZT4-7 310.62467749999996 310.62467749999996 310.62467749999996 ZT8-11 217.0256225 217.0256225 217.0256225 ZT12-15 139.387648 139.387648 139.387648 ZT16-19 102.438931 102.438931 102.438931 ZT20-23 134.692423 134.692423 134.692423