condition mean min max ZT0-3 260.038821 260.038821 260.038821 ZT4-7 281.6823945 281.6823945 281.6823945 ZT8-11 235.896475 235.896475 235.896475 ZT12-15 248.709404 248.709404 248.709404 ZT16-19 190.7720525 190.7720525 190.7720525 ZT20-23 192.590513 192.590513 192.590513