How Growth Trend Works

[Johnson]

Hi All,

I am having trouble understanding how Custom Fill - Growth Trend works in
Excel 2003.

The data I have is:

$ 23114 $24567 $22874 $27211

When I seelect all those 4 cells, then right drag across 5 more cells and
select Growth Trend, the results are:

$27069 $28225 $29430 $30687 $31997

I am confused as to how Excel arrives at those results i.e. what is the
calculation it uses to get those numbers? Why is the first forecasted value
($27069) 99% of the previous value then the rest are 104% of their preceeding
values?

Any help would be greatly appreciated, Johnson

 

[Mike Middleton]

Johnson -

The values are determined using an exponential fit (like the Add Trendline
exponential function on a chart).

You can get the same results using the array-entered worksheet function
GROWTH(known_y's,known_x's,new_x's,const)
where known_y's are your four values,
known_x's are 1,2,3,4,
new_x's are 5,6,7,8,9, and
const is True.

- Mike
www.mikemiddleton.com

 

[Johnson]

Thanks for the help!!

Johnson -

The values are determined using an exponential fit (like the Add Trendline
exponential function on a chart).

You can get the same results using the array-entered worksheet function
GROWTH(known_y's,known_x's,new_x's,const)
where known_y's are your four values,
known_x's are 1,2,3,4,
new_x's are 5,6,7,8,9, and
const is True.

- Mike
www.mikemiddleton.com