condition mean min max ZT0-3 2.186635 2.186635 2.186635 ZT4-7 3.019725 3.019725 3.019725 ZT8-11 1.651135 1.651135 1.651135 ZT12-15 0.0 0.0 0.0 ZT16-19 2.651115 2.651115 2.651115 ZT20-23 1.307395 1.307395 1.307395