How to format the legend of a chart
On Format Chart, select Show Legend to display a legend for the chart. If you do not select this box, the legend does not appear on the chart. In Position, select an option from the list to place the legend above, below, to the right, left, or inside the chart.
Type a title for the legend. If you leave this field blank, no legend title appears on the chart. In some cases, you can also specify font properties for the legend title and each legend item.

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