When defining chart appearance, you can specify a title and then select font and background options for the title.
To define a chart title:
From the Chart Properties property sheet, click the Format Chart button.
Optional: Click the Font button, , then set font options and click OK.
Optional: Click the Borders and Background icon, , then specify border and background options for the chart title, and click OK.
To place a border around the chart, select the Chart Border check box.
Optional: Click the Borders and Background icon, , then specify border and background options for the chart border and click OK.