In the table that corresponds to the chart, do any of the following:
Change or delete data: Select the cell that contains the data you want to change, then enter the new data or press Delete.
Add data: Insert a row or column inside the range of cells that was originally selected for the chart, then type the new data.
You need to add the new rows or columns of data within the chart’s current range of cells for it to show in the existing chart. For example, if the data plotted in a chart comes from rows 1-5, you must insert the new data between rows 1 and 5, not before or after.
To add more data points outside the current range of cells, or to use a different data series, delete the existing chart and add a new chart based on the table cells you select.