     width = 480 - margin.left - margin.right
     height = 480 - margin.top - margin.bottom
     
-    constructor: (@xm=0, @ym=0.4) ->
+    constructor: (@xm=0, @ym=0.8) ->
         super "plot"
 
         chartArea = @obj

        chartArea.append("g")
            .attr("class", "axis")
            .attr("transform", "translate(#{margin.left}, #{margin.top+height-110})")
            .call(@xAxis) 

        chartArea.append("g")
            .attr("class", "axis")

        x = Trans.X2x @pos.x
        y = Trans.fn x, plot.xm, plot.ym
        @limit =  Trans.y2Y y
        @bin = Math.floor((y+1)*20/2)  
 
    collision: -> @pos.y > @limit

