condition mean min max ZT0-3 21.400000000000002 21.400000000000002 21.400000000000002 ZT4-7 39.8 39.8 39.8 ZT8-11 40.05 40.05 40.05 ZT12-15 25.35 25.35 25.35 ZT16-19 26.25 26.25 26.25 ZT20-23 7.300000000000001 7.300000000000001 7.300000000000001