condition mean min max ZT0-3 13.4204265125 11.73997552 15.100877505 ZT4-7 14.33430134 13.570853825 15.097748855 ZT8-11 12.518508635 12.210727095 12.826290175 ZT12-15 5.690480738749999 4.5221244835 6.858836993999999 ZT16-19 8.537189711249999 7.491516128 9.5828632945 ZT20-23 15.18893069 12.152624445 18.225236934999998