condition mean min max ZT0-3 8.810229 8.810229 8.810229 ZT4-7 8.856889 8.856889 8.856889 ZT8-11 9.0409995 9.0409995 9.0409995 ZT12-15 9.10712 9.10712 9.10712 ZT16-19 9.259827 9.259827 9.259827 ZT20-23 9.8729495 9.8729495 9.8729495