         var maxY:Number = 0;     
         var firstColInView:int = -1;
         var lastColInView:int = -1;
+
+        // columnWidth can be expensive to compute
+        var cw:Number = (variableColumnWidth) ? 0 : columnWidth;
+                
         
         for (var index:int = 0; index < count; index++)
         {

    }    
    
    //----------------------------------
    //  explicitColumnWidth
    //----------------------------------

    /**
     *  The column width requested by explicitly setting
     *  <code>columnWidth</code>.
     */
    protected var explicitColumnWidth:Number;

    //----------------------------------
    //  columnWidth
    //----------------------------------
    
    private var _columnWidth:Number = 20;

    [Inspectable(category="General")]

    /**
     *  Specifies the width of the columns if <code>variableColumnWidth</code>
     *  is false.
     *  
     *  @default 20
     */
    public function get columnWidth():Number
    {
        return _columnWidth;
    }

    /**

            layoutItem.setActualPosition(x, y);
            var dy:Number = layoutItem.actualSize.y;
            if (!variableColumnWidth)
                layoutItem.setActualSize(cw, dy);

            // Update maxX,Y, first,lastVisibleIndex, and x
            var dx:Number = layoutItem.actualSize.x;
