Excel highlights the data range of a chart under many conditions. The source data range must be relatively simple, based on a rectangular data range. The chart must be embedded in the worksheet that also contains the data. If the data meets these conditions (elaborated upon later), selecting the chart area or the plot area of the chart will cause Excel to highlight the source data.
Highlighting is used in Excel versions 97 (or earlier) through 2007; Excel 2003 was used for the illustrations in this post. [Read more…] about Highlighted Chart Source Data