How much CPU time do B+ proggies use?

Using WaitEvent() etc.. in B+ I find CPU time at 0% usage when viewed from Task Manager.

Even this example takes up next to nothing:

; canvas window

Const w=640 , h=480

; setup the window and canvas
win=CreateWindow("Canvas Window",160,120,w,h,Desktop(),3)
can=CreateCanvas(0,0,ClientWidth(win)+8,ClientHeight(win)+29,win)
SetGadgetLayout can,1,1,1,1
SetBuffer CanvasBuffer(can)

Repeat
	Select WaitEvent(1)
		Case $803 : Exit
		Case $103 : If EventData()=27 Exit
		Default
		Cls
		Oval Rand(w),Rand(h),50,50
		FlipCanvas can
	End Select
Forever
End