condition mean min max ZT0-3 12.350000000000001 12.350000000000001 12.350000000000001 ZT4-7 33.7 33.7 33.7 ZT8-11 21.7 21.7 21.7 ZT12-15 11.05 11.05 11.05 ZT16-19 29.400000000000002 29.400000000000002 29.400000000000002 ZT20-23 26.6 26.6 26.6