condition mean min max ZT0-3 4.458078333333333 3.9493799999999997 4.93419 ZT4-7 3.2322300000000004 3.2322300000000004 3.2322300000000004 ZT8-11 5.62834 5.62834 5.62834 ZT12-15 5.5941975 3.91571 7.272685 ZT16-19 2.867865 2.867865 2.867865 ZT20-23 4.298405 4.298405 4.298405