condition mean min max ZT0-3 2.7496816666666666 0.0 4.14199 ZT4-7 0.0 0.0 0.0 ZT8-11 0.0 0.0 0.0 ZT12-15 1.9321525 0.0 3.864305 ZT16-19 3.697995 3.697995 3.697995 ZT20-23 0.0 0.0 0.0