condition mean min max ZT0-3 13.007921 13.007921 13.007921 ZT4-7 12.4276975 12.4276975 12.4276975 ZT8-11 12.7098555 12.7098555 12.7098555 ZT12-15 10.941649 10.941649 10.941649 ZT16-19 11.223483 11.223483 11.223483 ZT20-23 12.4491865 12.4491865 12.4491865