I have a spredsheet that keeps track of a number of sales items for every
month.

These sales numbers are also used for the sources in a chart that will give
me a visual picture of what is going on. So, if the spreadsheet has numbers
in A1 to C3, the source will be A1:C3

Each month I will add a new row to the spreadsheet for the new set of
numbers. Then in the chart I will have to manually change the source to A1:C4
and so on for each new month.

Is there a way to automatically have the chart to know that there is a new
row in the spreadsheet and automaically add that new row to the source?

To initially mark the source as A1:C100 or something like this is not
acceptible.

Thanks in advance

Charles.