condition mean min max ZT0-3 1.1692666666666667 0.424585 1.80289 ZT4-7 0.7088205 0.7088205 0.7088205 ZT8-11 1.368949 1.368949 1.368949 ZT12-15 4.684637499999999 4.037475 5.331799999999999 ZT16-19 3.7834000000000003 3.7834000000000003 3.7834000000000003 ZT20-23 2.15612 2.15612 2.15612