condition mean min max ZT0-3 387.363147 387.363147 387.363147 ZT4-7 301.039749 301.039749 301.039749 ZT8-11 343.34051850000003 343.34051850000003 343.34051850000003 ZT12-15 349.6169065 349.6169065 349.6169065 ZT16-19 471.07614149999995 471.07614149999995 471.07614149999995 ZT20-23 455.7107535 455.7107535 455.7107535