I'm working on a worksheet that already has formulas listed and I don't
understand one of the formulas. FYI...all the formulas I'm listing equals a
total number of units.

The formula in row 2 is written CZ1:CZ2-AS2.
The formula in row 3 is written CZ2:CZ3-AS3, etc.

CZ 1 is blank because it's a part of the header, CZ2 = 320, CZ3 = 267, AS2
= 320, and AS3 = 267

I get that the author wants to compare that the original total of units (AS2
or AS3) matches what is in CZ2 or CZ3. The end result should be zero if the
units match.

What I don't get is why is one row being compared to a previous row.

Have any of you ever seen a formula like this? And it doesn't follow the
mathematical rules for me either. I'm assuming it's taking the sum of CZ1 &
CZ2 then subtracting AS2 from the total, but I don't understand how the end
result is always zero.

Please help. It's quite possible there's an error with the formula, but I
wanted to know if you all have ever seen a formula like the one metioned
above.

Thanks,