How to show negative percentage?

If I divide two negative numeric cells and put the result into a
percentage cell, it will positive, even if the change is negative. For
example:

A B
1 -6249 -5810

A1/B1 = 107.56%

The change is moving from B to A. That means I should have a negative
change. How can I show that?

Thanks,
Brett

Harlan Grove is pretty smart.

Biff

"brett" <account@cygen.com> wrote in message
news:1136689645.874911.24280@g49g2000cwa.googlegroups.com...
> If I divide two negative numeric cells and put the result into a
> percentage cell, it will positive, even if the change is negative. For
> example:
>
> A B
> 1 -6249 -5810
>
> A1/B1 = 107.56%
>
> The change is moving from B to A. That means I should have a negative
> change. How can I show that?
>
> Thanks,
> Brett
>

On 8 Jan 2006 18:19:12 -0800, "brett" <account@cygen.com> wrote:

>If I divide two negative numeric cells and put the result into a
>percentage cell, it will positive, even if the change is negative. For
>example:
>
> A B
>1 -6249 -5810
>
>A1/B1 = 107.56%
>
>The change is moving from B to A. That means I should have a negative
>change. How can I show that?
>
>Thanks,
>Brett

You could always multiply your answer by -1. However, a "negative" percentage
is not generally a meaningful concept.

What real world problem are you trying to solve?


--ron

"brett" wrote:
> If I divide two negative numeric cells and put the
> result into a percentage cell, it will positive, even
> if the change is negative. For example:
> A B
> 1 -6249 -5810
> A1/B1 = 107.56%
> The change is moving from B to A. That means I
> should have a negative change.

What makes you think so? -5810*107.56% is -6249,
the correct answer. If you used -107.56% arbitrarily,
you would get +6249, which is wrong.

> How can I show that?

Since your choice of negative "change" (factor)
seems arbitrary, I don't know what you would
want in all cases -- for example, B is 2 and A is
-4, and B is -2 and A is 4. Note that when B is
4 and A is 2, the "change" (factor) should not
be negative.

Your request makes more sense to me when we
are talking about actual change, not growth factor.
Whenever A is less than B, we might reasonably
want to express the percentage change as negative.
But we must use that notion of change carefully.
For example:

To compute percentage change (C1):

=IF(B1=0, A1, SIGN(A1-B1)*ABS((A1-B1)/B1))

To apply (use) percentage change to B1 (D1),
which should equal A1:

=IF(B1=0, C1, B1+SIGN(C1)*ABS(C1*B1))

Examples (B1=before, A1=after):

A1 B1 C1 D1 (should = A1)
2 4 -50% 2
4 2 100% 4
-2 -4 50% -2
-4 -2 -100% -4
2 -4 150% 2
-4 2 -300% -4

Some people will quibble with my choice when B1=0.
It is arbitrary.