How to calculate compound percentage change

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To calculate the final percent change over a period with varying percentage changes, multiply the factors derived from each percentage change. For example, for a 3% increase, use 1.03, and for a 3% decrease, use 0.97. The overall formula is 100 times the product of these factors minus one. This method allows for efficient calculation without needing to compute each year's change individually. Understanding how to incorporate both increases and decreases is crucial for accurate results.
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Example: Inflation over time
Supposed that I want calculate the final percent change in a 10 year period.

(year , % Change) --> (1,3) (2,4) (3,7) (4,3) (5,2) (6,5) (7,4) (8,3) (9,4) (10,6)

How should I calculate the final percent inflation without having to calculate one by one?
 
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100 ( 1.03 * 1.04 * 1.07 ... * 1.06 -1 )
 
sorry for my laziness but how would you calculate with negative values?
 
Each term in the above product is (1 + %change/100).

So for a 3% change (increase) the product term is 1.03, for a 3% decrease you would use 0.97 and so on.
 
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