By default Impact's document merge merge engine uses standard formatting for decimal fields in ACT! These fields will look formatted as such "1,123". You can change the formatting rules globally by modifying a configuration file.

To see more formatting options please read Printing Format 

1) Close ACT!
2) Go to START - Durkin Impact v4 -> Durkin.Common.DocEngine
3) Edit the file "Generic.v4.Config.xml" using NotePad.exe
4) Find this section and change the value from  {0:n} to {0:n4}
5) Save the changes then restart ACT!

See also