condition mean min max ZT0-3 6.604165 6.604165 6.604165 ZT4-7 4.4636499999999995 4.4636499999999995 4.4636499999999995 ZT8-11 3.63267 3.63267 3.63267 ZT12-15 4.202585 4.202585 4.202585 ZT16-19 7.77977 7.77977 7.77977 ZT20-23 6.0576 6.0576 6.0576