A yellow bar representing the 
value added appears
					on top of the blue system bar. A tooltip on the system bar gives detailed
					information, including the 
value added for the system
					(50%). 
						

					
Value added for the system and operations is also displayed in the
							Value Added column. 
					Note:
			System value added=Sum(Operation
								value added*Operation duration)/(total
							time)=(60*10+40*10)/20=50%.