condition mean min max ZT0-3 1.884725 1.1529449999999999 2.785555 ZT4-7 2.427135 2.427135 2.427135 ZT8-11 0.9259580000000001 0.9259580000000001 0.9259580000000001 ZT12-15 1.9255799999999998 1.73495 2.1162099999999997 ZT16-19 2.099265 2.099265 2.099265 ZT20-23 1.731655 1.731655 1.731655