condition mean min max ZT0-3 1.1588115 0.9507855000000001 1.325755 ZT4-7 1.2308375 1.2308375 1.2308375 ZT8-11 1.60492 1.60492 1.60492 ZT12-15 1.0554375 0.8877550000000001 1.22312 ZT16-19 0.9653510000000001 0.9653510000000001 0.9653510000000001 ZT20-23 1.22685 1.22685 1.22685