What is the first step to set the last data point as a total in a chart element?

To set the last data point as a total in a chart element, the process involves directly interacting with the chart that presents the relevant data. By double-clicking on the September Net Income chart element, you initiate the editing mode for that specific chart. This is a crucial step, as it allows you to access chart properties and make necessary adjustments.

When you double-click the chart, you typically open a formatting interface where options for adjusting how data is displayed are available, including the ability to specify how totals should be presented. Identifying and focusing on the relevant chart element is essential for applying features like setting a last data point as a total.

The other options do not effectively initiate the process of modifying chart data presentation. For example, opening the Macro dialog or running a specific macro does not provide direct access to the chart's properties needed to change how totals are displayed. Checking a box like "Set as total" is only possible once you are in the right editing context, which is achieved by interacting directly with the chart itself. Therefore, double-clicking the chart element is the foundational action needed to proceed with any further modifications regarding totals.