Neither AutoSum nor the SUM function ignores errors. If there is an error in
a cell, AutoSum will not reference cells above that cell. The SUM function
will return the same error as exists in any of its input cells. To SUM a
range and ignore errors, use the following array formula

=SUM(IF(ISNUMBER(A1:A10),A1:A10))

This will return the SUM of A1:A10, ignoring error values. Change both
instances of "A1:A10" to your range.

Since this is an array formula, you MUST press CTRL+SHIFT+ENTER rather than
just ENTER when you first enter the formula and whenever you edit it later.
If you do this properly, Excel will display the formula enclosed in curly
braces { }.

For more info about array formulas, see www.cpearson.com/excel/array.htm .


--
Cordially,
Chip Pearson
Microsoft MVP - Excel
Pearson Software Consulting
www.cpearson.com
(email on the web site)


"Robojohn" wrote in message
...
I need to show a total for a series of values.
Some of these values may be replaced with "N/A" as a result of an IF
formula.
When this happens, the total does not always calculate, which has a
knock-on
effect for other formulas.

Any ideas?