condition mean min max ZT0-3 36.05123333333333 29.68075 46.633449999999996 ZT4-7 36.7394 36.7394 36.7394 ZT8-11 25.12865 25.12865 25.12865 ZT12-15 30.974525000000003 26.112000000000002 35.837050000000005 ZT16-19 21.4925 21.4925 21.4925 ZT20-23 27.368450000000003 27.368450000000003 27.368450000000003