editing excel file through shell script

Hi,

I am having a business file in excel having charts based on data already present on it. I would like to add new rows after the existing data and refesh the chart on it using shell script.

For example--
In excel file in "sheet1", There is some data in first 10 rows ( from column A to F). Now I want to add data on 11th row keeping existing data intact. Also if possible already present chart on sheet1 must be refreshed to reflect newly added row.

Please help.

Thanx.