condition mean min max ZT0-3 3.45223 3.45223 3.45223 ZT4-7 2.760195 2.760195 2.760195 ZT8-11 3.816535 3.816535 3.816535 ZT12-15 4.0286100000000005 4.0286100000000005 4.0286100000000005 ZT16-19 6.6097850000000005 6.6097850000000005 6.6097850000000005 ZT20-23 3.563795 3.563795 3.563795