Sum of average growth

[Adragoon]

Hi, I'm new to the forums and was wondering if someone could help me.


I need to find the average growth rate and can't seem to figure out a simple formula for it. For example:


B1 = 3
B2 = 6
B3 = 9


=Sum((B3/B2)+(B2/B1))


Is there a simpler formula for this? I have a rather large pool of data.


Thanks for your help!

 

[BiocideJ]

First off, welcome to the forum!
In answer to your question, the SUMPRODUCT formula does pretty much what you are asking.

the equivalent to your formula would be
=SUMPRODUCT(B2:B3/B1:B2)

If you have a range of values from B1:B100 your formula would be
=SUMPRODUCT(B2:B100/B1:B99)

Note that the two ranges are the same size, but just offset by one row.