Mail merge in Word cannot really hand a multiple items (transactions in your
case) per condition (Employee in your case) situation.

If you have Microsoft Access, I would recommend transferring the data into
Access and then use an Access Report.

Otherwise, you could try further developing the following macro.  It would
take some work, but it would be quite feasible to get it to do what you
want.

' Macro to create multiple items per condition from a directory type
mailmerge

Dim source As Document, target As Document, scat As Range, tcat As Range
Dim data As Range, stab As Table, ttab As Table
Dim i As Long, j As Long, k As Long, n As Long
Set source = ActiveDocument
Set target = Documents.Add
Set stab = source.Tables(1)
k = stab.Columns.Count
Set ttab = target.Tables.Add(Range:=Selection.Range, numrows:=1,
numcolumns:=k - 1)
Set scat = stab.Cell(1, 1).Range
scat.End = scat.End - 1
ttab.Cell(1, 1).Range = scat
j = ttab.Rows.Count
For i = 1 To stab.Rows.Count
   Set tcat = ttab.Cell(j, 1).Range
   tcat.End = tcat.End - 1
   Set scat = stab.Cell(i, 1).Range
   scat.End = scat.End - 1
   If scat <> tcat Then
       ttab.Rows.Add
       j = ttab.Rows.Count
       ttab.Cell(j, 1).Range = scat
       ttab.Rows.Add
       For n = 2 To k
           Set data = stab.Cell(i, n).Range
           data.End = data.End - 1
           ttab.Cell(ttab.Rows.Count, n - 1).Range = data
       Next n
   Else
       ttab.Rows.Add
       For n = 2 To k
           Set data = stab.Cell(i, n).Range
           data.End = data.End - 1
           ttab.Cell(ttab.Rows.Count, n - 1).Range = data
       Next n
   End If
Next i