condition mean min max ZT0-3 0.31885066666666667 0.1368205 0.5439025 ZT4-7 0.5830505 0.5830505 0.5830505 ZT8-11 0.8210545 0.8210545 0.8210545 ZT12-15 1.964335 1.5953 2.33337 ZT16-19 1.534595 1.534595 1.534595 ZT20-23 0.9621005 0.9621005 0.9621005