How Can I count the number of changes in DDE data
 

I am using Excel 97 and importing DDE data into a workbook. There are several
items of related data which I use to create charts.
Using automatic Updating my spreadsheets display most of what I need but
I want to make cells update every time a change is detected in each item of
data.

This will allow me to produce a bar chart which updates continuously
comparing the number of changes for each source.

I cant find any way to do this other than by using a Macro but this would
suspend other Excel actiity and as the data changes typically every 2 to 5
seconds this would not help.

I can then reset the count at regular intervals and the bar chart would give
me a comparison of the activity form each data source, which is what I need.