Cell.Formula Method
Word Developer Reference 
Syntax
expression.Formula(Formula, NumFormat)
expression Required. A variable that represents a Cell object.
Parameters
Name  Required/Optional  Data Type  Description 

Formula  Optional  Variant  The mathematical formula you want the = (Formula) field to evaluate. Spreadsheettype references to table cells are valid. For example, "=SUM(A4:C4)" specifies the first three values in the fourth row. For more information about the = (Formula) field, see Field codes:= (Formula) field. 
NumFormat  Optional  Variant  A format for the result of the = (Formula) field. For information about the types of formats you can apply, see Numeric Picture (\#) field switch. 
Remarks
Formula is optional as long as there is at least one cell that contains a value above or to the left of the cell that contains the insertion point. If the cells above the insertion point contain values, the inserted field is {=SUM(ABOVE)}; if the cells to the left of the insertion point contain values, the inserted field is {=SUM(LEFT)}. If both the cells above the insertion point and the cells to the left of the insertion point contain values, Microsoft Word uses the following rules to determine which SUM function to insert:
 If the cell immediately above the insertion point contains a value, Word inserts {=SUM(ABOVE)}.
 If the cell immediately above the insertion point doesn't contain a value and the cell immediately to the left of it does, Word inserts {=SUM(LEFT)}.
 If neither adjoining cell contains a value, Word inserts {=SUM(ABOVE)}.
 If you don't specify Formula and all the cells above and to the left of the insertion point are empty, the result of the field is an error.
Example
This example creates a 3x3 table at the beginning of the active document and then averages the numbers in the first column.
Visual Basic for Applications 


This example inserts a formula at the insertion point that determines the largest number in the cells above the selected cell.
Visual Basic for Applications 

