condition mean min max ZT0-3 7.950525 7.950525 7.950525 ZT4-7 7.3190349999999995 7.3190349999999995 7.3190349999999995 ZT8-11 7.683205 7.683205 7.683205 ZT12-15 5.868545 5.868545 5.868545 ZT16-19 9.47005 9.47005 9.47005 ZT20-23 8.1033 8.1033 8.1033