condition mean min max ZT0-3 3.396455 3.396455 3.396455 ZT4-7 3.871595 3.871595 3.871595 ZT8-11 3.11611 3.11611 3.11611 ZT12-15 1.934425 1.934425 1.934425 ZT16-19 3.422175 3.422175 3.422175 ZT20-23 2.6425799999999997 2.6425799999999997 2.6425799999999997