Previously Zoom in and out were not equal scale when we use scroll mouse wheel. But now it is equal. when we working in model or paper space, we can guess letter sizes and every other annotating parameters by getting the drawing zooming in/out with matching our small size papers by visual, because we can take the drawing area in to different scales by mouse wheel.Now I have experienced zoom in and zoom out equal and  we cannot do that.Please correct me. 

I dont't have any idea.