condition mean min max ZT0-3 929.68777 929.68777 929.68777 ZT4-7 1021.0595055 1021.0595055 1021.0595055 ZT8-11 1171.870133 1171.870133 1171.870133 ZT12-15 1336.9765915 1336.9765915 1336.9765915 ZT16-19 930.424708 930.424708 930.424708 ZT20-23 861.3791565 861.3791565 861.3791565