chart not updating
 

I am using Excel 2003, I have a data in one worksheet which links to another
worksheet, I then have a chart which is based of the second worksheet. When
I change the data form the first worksheet, it does update the second one,
but does update the chart. My source data is correct, and I have it set to
autmatic for calculations. F9 function also does not work, the chart will
only update if I save, close and reopen. Is there something I can do, to
make this update automatically?
Thanks