condition mean min max ZT0-3 10.90755 10.90755 10.90755 ZT4-7 6.602545 6.602545 6.602545 ZT8-11 4.45842 4.45842 4.45842 ZT12-15 7.9326099999999995 7.9326099999999995 7.9326099999999995 ZT16-19 14.810649999999999 14.810649999999999 14.810649999999999 ZT20-23 16.55685 16.55685 16.55685