condition mean min max ZT0-3 12.966558333333333 7.332875 16.89795 ZT4-7 5.550364999999999 5.550364999999999 5.550364999999999 ZT8-11 4.20289 4.20289 4.20289 ZT12-15 6.8884275 6.388285 7.38857 ZT16-19 10.4627 10.4627 10.4627 ZT20-23 14.308499999999999 14.308499999999999 14.308499999999999