Adding the totals of two seperate tables in a word document - ms-word

Question

this question relates to adding the totals of two tables and using that total in the body of the word document.
In my case I have a word document (docx) with two tables. These tables are populated through a word merge process of third party software over which I have no control. For ease of reference I will refer to each table as table1 and table2. Both tables will contain an unknown amount of rows, but the last row, will always contain a total in the last column, which will total the rows above using the formula =SUM(ABOVE).
In the body of the document, I know need to reference the total of each table and because I do not know how many rows there are, I am at a loss. For example, if I knew how many rows there are, I could use the answer given here.
I have tried to using a merge field - with the column names as follows - however I get a !Syntax error ...
=SUM(table1[Amount]+table2[InterestAmount])
Any and all help greatly appreciated.

Answer 1

If you bookmark the two tables (e.g. TblA, TblB), you can use a formula field to tally their totals:
{=SUM(TblA C:C)/2+SUM(TblB C:C)/2}
The reason for the /2 is that, unless you know the last row # beforehand, you need to reference the entire column (including your existing totals row), the sum of which will therefore be twice the total.
To see how to do a wide range of calculations in Word, check out my Microsoft Word Field Maths Tutorial, at:
http://www.msofficeforums.com/word/38720-microsoft-word-field-maths-tutorial.html
or:
http://www.gmayor.com/downloads.htm#Third_party

Answer 2

Fields can be bookmarked in Word, then referenced elsewhere in the document. When bookmarking in a table, be careful to not select the entire cell, only the field! If the entire cell is bookmarked then the cell structures are carried across to the REF and the field content can't be processed numerically.
For three bookmarked fields with the names Fld1, Fld2and Fld3 that should be multiplied the combined field code would look like this:
{ = { REF Fld1 } * { REF Fld2 } * { REF Fld3 } \# "0.00" }
Note that you could also use the PRODUCT function (like SUM, but multiplies, each factor separated using the system's list separator character.)
Notes for readers not familiar with working with Word field codes: the paired wavy braces must be inserted using Ctrl+F9 and cannot simply be typed from the keyboard. Alt+F9 will toggle between field code and field result display. Press F9 to force a field to update.