condition mean min max ZT0-3 1.192865 1.192865 1.192865 ZT4-7 0.6960109999999999 0.6960109999999999 0.6960109999999999 ZT8-11 0.5469205 0.5469205 0.5469205 ZT12-15 1.438445 1.438445 1.438445 ZT16-19 2.969135 2.969135 2.969135 ZT20-23 1.600865 1.600865 1.600865