condition mean min max ZT0-3 60.221324 60.221324 60.221324 ZT4-7 71.31248500000001 71.31248500000001 71.31248500000001 ZT8-11 79.2623995 79.2623995 79.2623995 ZT12-15 83.3626575 83.3626575 83.3626575 ZT16-19 80.40969100000001 80.40969100000001 80.40969100000001 ZT20-23 77.072629 77.072629 77.072629