condition mean min max ZT0-3 21.4617 21.4617 21.4617 ZT4-7 20.35755 20.35755 20.35755 ZT8-11 18.4377 18.4377 18.4377 ZT12-15 19.1051 19.1051 19.1051 ZT16-19 22.17825 22.17825 22.17825 ZT20-23 21.7872 21.7872 21.7872