Assuming you data is in A1:A4, one way:

B2: =A2/A1-1 ==== 10%
B3: =A3/A2-1 ==== 36.36%
B4: =A4/A3-1 ==== 33.33%

If by "average monthly increase" you mean the average of the individual
monthly increases, that's just

=AVERAGE(B2:B4) === 26.57%

OTOH, if by "average monthly increase" you mean the constant monthly
increase that, when applied to 50, yields 100 after 3 months, then use

=(A4/A1)^(1/3) - 1 == 25.99%



In article ,
vikgarden wrote:

Not sure how to do this, If I have a range of numbers, (50, 55, 75, 100)
Percentage of increase is (10%, 36%, 33%)
Average monthly increase is 26%

How do I get excel to calculate the above?