condition mean min max ZT0-3 20.007216666666665 14.85935 25.49945 ZT4-7 17.2816 17.2816 17.2816 ZT8-11 7.6073450000000005 7.6073450000000005 7.6073450000000005 ZT12-15 6.74706 5.190645 8.303475 ZT16-19 5.257875 5.257875 5.257875 ZT20-23 11.177299999999999 11.177299999999999 11.177299999999999