condition mean min max ZT0-3 0.8789531666666667 0.584665 1.030771 ZT4-7 1.485055 1.485055 1.485055 ZT8-11 1.1802495 1.1802495 1.1802495 ZT12-15 0.82864675 0.2213985 1.435895 ZT16-19 1.1069315 1.1069315 1.1069315 ZT20-23 0.632741 0.632741 0.632741