condition mean min max ZT0-3 20.951818333333335 8.385905000000001 27.31915 ZT4-7 10.10032 10.10032 10.10032 ZT8-11 12.959150000000001 12.959150000000001 12.959150000000001 ZT12-15 24.488125 22.76415 26.2121 ZT16-19 24.221 24.221 24.221 ZT20-23 35.74325 35.74325 35.74325