condition mean min max ZT0-3 8.74812 8.74812 8.74812 ZT4-7 7.5238 7.5238 7.5238 ZT8-11 9.037645 9.037645 9.037645 ZT12-15 8.026195000000001 8.026195000000001 8.026195000000001 ZT16-19 8.947895 8.947895 8.947895 ZT20-23 7.7513950000000005 7.7513950000000005 7.7513950000000005