condition mean min max ZT0-3 8.27366737525 6.5747081860000005 9.9726265645 ZT4-7 16.242853682499998 13.597864004999998 18.887843359999998 ZT8-11 13.277630945 12.739290924999999 13.815970965000002 ZT12-15 5.227326006749999 3.3308921414999997 7.123759871999999 ZT16-19 5.256806779 4.261499284499999 6.2521142735 ZT20-23 8.695305600000001 8.4424460295 8.948165170500001