Excel chart not updating after the underlying data range changes

Hi,

I was not having this issue until recently. I have a chart which depends on a data range. This data range gets data from a webquery. When I click on 'refresh all', the data is updating; but the chart is not updating until I save the file. I was not having this issue earlier. It used to update the chart without saving the file. Can you please help? Attached the excel file.

NB:I am using excel 2007. Attached the version info also.