condition mean min max ZT0-3 2.3907883333333335 1.443095 3.07303 ZT4-7 1.79785 1.79785 1.79785 ZT8-11 2.049265 2.049265 2.049265 ZT12-15 3.5329275 3.338105 3.72775 ZT16-19 3.725145 3.725145 3.725145 ZT20-23 4.14363 4.14363 4.14363