condition mean min max ZT0-3 8.696633415250002 8.5030539135 8.890212917000001 ZT4-7 5.63893292625 5.5112666775 5.766599175 ZT8-11 4.8509496389999995 4.8020956895 4.899803588499999 ZT12-15 3.626338294 3.1212464495 4.1314301385 ZT16-19 3.5353096895 3.5304884935 3.5401308855 ZT20-23 4.0107505347500005 3.6450693870000004 4.3764316825