# possible bug in addition of formula result if result is "" (blank)

I have a small spreadsheet that shows this problem and if I can figure out how to attach it or upload it I will.

The problem I'm seeing is this: I have a formula that generates either a blank or a number. The result of this formula is added to another number. If the formula generates a blank the result of cell+cell is #value, but the result of sum(cell:cell) is correct.

Looks like I can't upload an example SS so here goes a long and tedious explanation. Please enter the following and you will see the problem:

Cell A1 1

Cell A3 1

Cell A4 blank (i.e. nothing in this cell)

Cell A5 3

Cell A6 =A3+A4+A5

Cell B3 1

Cell B4 =if(A1=1,"",2)

Cell B5 3

Cell B6 =B3+B4+B5

Cell C3 1

Cell C4 =if(A1=1,"",2)

Cell C5 3

Cell C6 =sum(C3:C5)

If you get the same result I got then you will see the following:

A6 4

B6 #VALUE!

C6 4

This looks like a bug to me. Somehow when the formula evaluates to "", addition fails, though a simple, non-formulaic "" works fine.

I'm hoping someone will either verify the problem and I'll report a bug, or explain to me what I'm doing wrong.