Horizontal line to show average in dygraph

[laurence]

I am trying to add a horizontal line to dygraph which already show my time series data.I have average of the complete data which I want to show as a static horizontal line on dygraph.Does anyone know how to do that simply.I already checked following links:http://dygraphs.com/tests/highlighted-region.htmlview-source:http://dygraphs.com/tests/crosshair.htmlThere must be some simple solution to this