Add a Symbol as an Overlay

Choosing As Overlay will overlay the chart, but the chart will have its own, independent price scale (y-axis).

Choosing Add to Existing Layer will overlay the chart and the chart will share the price scale (y-axis) with the existing chart on the active pane.  

1. Click on the chart to make it the active window.
    

2. From the Active Plug-In toolbar, position your cursor in the Symbol field, and type the desired symbol.
    

   You may enter:

   1. • the commodity symbol, month, and year (such as WZ03 or SPH4)
         

      • the front month (the futures delivery month with the soonest delivery date, or the option delivery month with the soonest expiration date). For the front month, enter the commodity code and the string "1!" (W1!, SP1!). Likewise, forward contracts may be selected using "2!" (2 months forward), "3!" (3 months forward), etc. (W2! or SP3!)
         

      • the symbol root (W, SP, etc.) for the front month
         

      • the symbol root prefaced with a percent sign (%W, %SP, etc.) to display a simple continuation chart
         

      • the symbol root prefaced with a percent sign (%W, %SP, etc.) plus additional parameters, to display a continuation chart: (%SP3!;2M;B)
         

      • an expression, using one or more contracts, numerical constants, and simple mathematical operators:

      • • DJY - SPY

        • C1! - W1!

        • SPY - %SP1!;4EH

        • (NG1! + NG2! + NG3!) / 3
           

3. Position your cursor on the Add button, click the arrow, and select As Overlay or Add to Existing Layer. (When the chart has multiple panes, you are asked which pane you want to add the overlay on.)