condition mean min max ZT0-3 47.032855 47.032855 47.032855 ZT4-7 66.084489 66.084489 66.084489 ZT8-11 75.7422335 75.7422335 75.7422335 ZT12-15 60.901934999999995 60.901934999999995 60.901934999999995 ZT16-19 60.6183945 60.6183945 60.6183945 ZT20-23 42.7265065 42.7265065 42.7265065