This is what the help files say about the NA function, which what you posted
is an alternate for (see the Remarks section)...

Returns the error value #N/A. #N/A is the error value that means "no value
is available." Use NA to mark empty cells. By entering #N/A in cells where
you are missing information, you can avoid the problem of unintentionally
including empty cells in your calculations. (When a formula refers to a cell
containing #N/A, the formula returns the #N/A error value.)

Syntax: NA( )

Remarks
===========
- You must include the empty parentheses with the function name. Otherwise,
Microsoft Excel will not recognize it as a function.

- You can also type the value #N/A directly into a cell. The NA function is
provided for compatibility with other spreadsheet programs.

--
Rick (MVP - Excel)


"Rick" wrote in message
...
I have in a cell =#N/A and it displays a value however I don't quite
understand what the formula is doing? Any insights?