condition mean min max ZT0-3 26.1357 26.1357 26.1357 ZT4-7 22.6937 22.6937 22.6937 ZT8-11 20.6603 20.6603 20.6603 ZT12-15 23.79875 23.79875 23.79875 ZT16-19 29.73455 29.73455 29.73455 ZT20-23 24.7797 24.7797 24.7797