condition mean min max ZT0-3 42.896425 42.5968 43.19605 ZT4-7 69.33485 69.33485 69.33485 ZT8-11 63.50875 63.50875 63.50875 ZT12-15 0 0 0 ZT16-19 42.669799999999995 42.669799999999995 42.669799999999995 ZT20-23 44.504850000000005 44.504850000000005 44.504850000000005