condition mean min max ZT0-3 5.609891666666667 3.5770100000000005 9.297255 ZT4-7 2.6175100000000002 2.6175100000000002 2.6175100000000002 ZT8-11 0.556361 0.556361 0.556361 ZT12-15 0.99810925 0.7284935 1.267725 ZT16-19 0.2993245 0.2993245 0.2993245 ZT20-23 1.45313 1.45313 1.45313