.graduatedPointForValue(v);
                      var geo = new go.Geometry(go.GeometryType.Line);
                      geo.startX = 100 + scale.margin.left;
                      geo.startY = 90 + scale.margin.top;
                      geo.endX = pt.x + scale.margin.left;
                      geo.endY = pt.y + scale.margin.top;
                      return geo;
                    })
                ),
              new go.TextBlock({
                alignment: new go.Spot(0.5, 0.5, 0, 20),
            