condition mean min max ZT0-3 5.938890000000001 5.938890000000001 5.938890000000001 ZT4-7 5.01784 5.01784 5.01784 ZT8-11 10.946549999999998 10.946549999999998 10.946549999999998 ZT12-15 6.28337 6.28337 6.28337 ZT16-19 6.867725 6.867725 6.867725 ZT20-23 3.88091 3.88091 3.88091