condition mean min max ZT0-3 38.650850000000005 31.2785 46.0232 ZT4-7 19.871850000000002 19.871850000000002 19.871850000000002 ZT8-11 15.98825 15.98825 15.98825 ZT12-15 0 0 0 ZT16-19 18.396900000000002 18.396900000000002 18.396900000000002 ZT20-23 25.6601 25.6601 25.6601