Answer:
5.83%
Step-by-step explanation:
You want the average annual revenue increase over the 4-year period in which the annual increases were 2.55%, 8.21%, 3.52%, and 9.21%.
Multiplier
If p was the percentage increase in a given year, it means the revenue was multiplied by (1+p). Then the multiplier over the four years of concern would be ...
(1 +p₁)·(1 +p₂)·(1 +p₃)·(1 +p₄)
Annual average
If the average annual percentage increase is x, then we have ...
(1 +p₁)·(1 +p₂)·(1 +p₃)·(1 +p₄) = (1 +x)⁴
Solving for x gives ...
[tex]x=\sqrt[4]{(1+p_1)(1+p_2)(1+p_3)(1+p_4)}-1[/tex]
The calculation of that value is shown in the attachment.
x ≈ 0.5833 ≈ 5.83%
The average annual increase in revenue was about 5.83%.
