condition mean min max ZT0-3 1.6993425 1.45692 1.941765 ZT4-7 1.2431195000000002 1.2431195000000002 1.2431195000000002 ZT8-11 2.02533 2.02533 2.02533 ZT12-15 0 0 0 ZT16-19 3.62725 3.62725 3.62725 ZT20-23 2.578945 2.578945 2.578945