How are you connecting to the Excel data source? If you have entered numbers
(say 100, 200, 300) in your Excel sheet then formatted them using Format
Cells to have 2 decimal places, the default connection method in Word
(OLEDB) will still see the numbers as 100, 200, 300. If you use DDE to
connect (check Word Tools|Options|General|"Confirm conversion at open" and
go through the connection process again, and select the DDE option when it
is offered) you will probably see the currency amounts the way you see them
in Excel. Or you can apply formatting in Word by using Alt-F9 to see the
field codes and changing, e.g.

{ MERGEFIELD mycurrency \*Mergeformat }

to e.g.

{ MERGEFIELD mycurrency \#"0.00" \*Mergeformat }

If absolutely nothing has changed in the way you are working and you haven't
installed any updates to Office etc., then it is certainly strange that the
behaviour of Word+Excel has changed, but the above approaches are the main
ways I know to fix the problem anyway.

Peter Jamieson