PS....

On Jan 24, 11:52 am, I wrote:
If A1 is an old value and B1 is a new value,
typically you would do: =(B1-A1)/A1

Technically, that gives the wrong answer when both values are
negative. But arguably, it depends on your point of view.

Consider profits that go from -100 to -50.

Technically, that is a 50% gain, which the formula =(B1-A1)/abs(A1)
correctly yields. Thus, that formula yields the correct result with
all combinations of positive and negative values.

But some people like to say that losses "decreased" by 50%. And =(B1-
A1)/A1 does yield that result (-50%).

IMHO, that terminology breaks down when the values differ in sign.
Consider two cases: (a) profits go from -50 to 50; and (b) profits go
from 50 to -50. In both cases, (B1-A1)/A1 yields -200%(!).

In contrast, (B1-A1)/abs(A1) yields 200% in the first case, and -200%
in the second case. IMHO, that makes better sense.


----- original posting -----

On Jan 24, 12:07*pm, joeu2004 wrote:
PS....

On Jan 24, 11:52 am, I wrote:

If A1 is an old value and B1 is a new value,
typically you would do: * =(B1-A1)/A1

More generally, really that is simply the percentage increase or
decrease from one number (A1) to another number (B1). *It is entirely
up to you whether A1 is the old number and B1 is the new number, or A1
is the new number and B1 is the old number.

----- original posting -----

On Jan 24, 11:52*am, joeu2004 wrote:

On Jan 24, 10:39*am, mary bono <mary wrote:

I am trying to find out how to create a formula
that will help me finda drop *in a percentage of
a number or an increase of a percentage.

If A1 is an old value and B1 is a new value, typically you would do:

=(B1-A1)/A1

But if A1 and B1 might have opposite signs (one negative, the other
positive), you would do:

=(B1-A1)/abs(A1)

Note that that works when the signs are the same as well (both
negative or both positive).

In both case, the old value (A1) cannot be zero. *There is no "right"
answer when the old value is 0. *But one approach might be:

=if(A1=0, sign(B1), (B1-A1)/abs(A1))

That returns 100% or -100% for any change when the old value is zero.

In all cases, format the cell as Percentage with an appropriate number
of decimal places.