Note also that neither { NUMWORDS } or { =B1/190 } fields update automatically. As they are in the footer you would either have to open the footer to update them or use a macro.
http://www.gmayor.com/installing_macro.htm
Code:
Sub UpdateAllFields()
Dim oStory As Range
For Each oStory In ActiveDocument.StoryRanges
oStory.Fields.Update
If oStory.StoryType <> wdMainTextStory Then
While Not (oStory.NextStoryRange Is Nothing)
Set oStory = oStory.NextStoryRange
oStory.Fields.Update
Wend
End If
Next oStory
Set oStory = Nothing
lbl_Exit:
Exit Sub
End Sub