condition mean min max ZT0-3 83.162012 83.162012 83.162012 ZT4-7 68.6764325 68.6764325 68.6764325 ZT8-11 62.005607999999995 62.005607999999995 62.005607999999995 ZT12-15 57.448546 57.448546 57.448546 ZT16-19 68.143798 68.143798 68.143798 ZT20-23 64.5771805 64.5771805 64.5771805