How to Plot Bid/Ask Spread Percent (%) as an Indicator (Stocks)
You can now add the Bid/Ask spread as an indicator to see the history of the bid/ask movement in any time frame.
1. Click the Add Plot to Chart button.

There are two other ways to open the Add Plot menu. 1) Use the forward slash "/" hot key to add indicators; 2) Right-click anywhere on the chart and choose Add Plot from the drop down menu.
2. Type Bid/Ask Spread

Use the search field to quickly look up items to plot.
3. Click on Bid/Ask Spread Percent Indicator

4. The Bid/Ask Spread % is plotted in the bottom pane

Click here for more about moving/arranging plots on your chart.