Click the Draw button to view available annotations that can be added to your chart, or open the right click context chart menu and select Add Drawing.
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Once you select a tool, click on the chart to start its placement. Any tools or annotations you add are always saved and will show the next time you view the chart. To change the color or parameters of a tool, right-click on the tool after its been placed on the chart.
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To delete a tool, click on the tool to select it, then press your delete key.