condition mean min max ZT0-3 3.3957550000000003 3.0129200000000003 3.77859 ZT4-7 4.7653099999999995 4.7653099999999995 4.7653099999999995 ZT8-11 3.7040249999999997 3.7040249999999997 3.7040249999999997 ZT12-15 0 0 0 ZT16-19 4.8655550000000005 4.8655550000000005 4.8655550000000005 ZT20-23 6.20728 6.20728 6.20728