condition mean min max ZT0-3 3.192559833333333 0.7277245000000001 4.679925 ZT4-7 0.8374365 0.8374365 0.8374365 ZT8-11 1.116025 1.116025 1.116025 ZT12-15 2.906645 2.87054 2.94275 ZT16-19 3.9498949999999997 3.9498949999999997 3.9498949999999997 ZT20-23 5.682645 5.682645 5.682645