condition mean min max ZT0-3 3.1122250000000005 2.053615 4.170835 ZT4-7 0.6352629999999999 0.6352629999999999 0.6352629999999999 ZT8-11 0.2178135 0.2178135 0.2178135 ZT12-15 0 0 0 ZT16-19 1.975025 1.975025 1.975025 ZT20-23 1.1960655 1.1960655 1.1960655