condition mean min max ZT0-3 579.536333 579.536333 579.536333 ZT4-7 534.283439 534.283439 534.283439 ZT8-11 459.021074 459.021074 459.021074 ZT12-15 465.4193375 465.4193375 465.4193375 ZT16-19 650.1744785000001 650.1744785000001 650.1744785000001 ZT20-23 786.343797 786.343797 786.343797