condition mean min max ZT0-3 1.9411875 1.6821700000000002 2.200205 ZT4-7 0.417267 0.417267 0.417267 ZT8-11 0.5425675 0.5425675 0.5425675 ZT12-15 0 0 0 ZT16-19 2.01715 2.01715 2.01715 ZT20-23 0.9763625 0.9763625 0.9763625