condition mean min max ZT0-3 2.39129857 0.48827345299999997 4.294323687 ZT4-7 24.686291050500003 16.869214851 32.503367250000004 ZT8-11 38.198428342499994 37.393586584999994 39.003270099999995 ZT12-15 29.81806741 28.722663145 30.913471675000004 ZT16-19 24.1824095625 23.88109053 24.483728595 ZT20-23 14.012303670500001 9.446237526 18.578369815000002