condition mean min max ZT0-3 1.18672 1.18672 1.18672 ZT4-7 0.973993 0.973993 0.973993 ZT8-11 1.2500300000000002 1.2500300000000002 1.2500300000000002 ZT12-15 0.9724085 0.9724085 0.9724085 ZT16-19 1.2609650000000001 1.2609650000000001 1.2609650000000001 ZT20-23 1.5349333333333333 1.5349333333333333 1.5349333333333333