How to calculate percent of change

Understanding how to calculate the percent of change is an essential skill for numerous real-life situations, from analyzing financial data to tracking the progress of various key performance indicators (KPIs) in business. In this article, we will outline a straightforward approach to calculating percent of change, providing a step-by-step guide and practical examples to help you master this concept.
Defining Percent of Change
The percent of change represents the relative growth or decrease between two values, typically expressed as a percentage. Calculating it will indicate the magnitude of the change and can be helpful in comparing variations among different datasets.
Step-by-Step Guide for Calculating Percent of Change
1. Identify the initial and final values: Determine which value represents the starting point (initial value), often referred to as the “old value” or Value1, and which one corresponds to the ending point (final value), also known as the “new value” or Value2.
2. Calculate the difference: Subtract the initial value from the final value. Mathematically, this can be represented as:
Difference = Value2 – Value1
3. Divide the difference by the initial value: To find the proportional change, divide the difference calculated in Step 2 by the initial value:
Proportional Change = Difference / Value1
4. Convert proportional change to percentage: Multiply the proportional change by 100 to express it as a percentage:
Percent of Change = Proportional Change * 100
That’s it! The resulting figure represents the percent of change between your initial and final values.
Examples
1. Imagine that a stock’s price increased from $50 to $70 over one year. To calculate its percent of change:
Initial Value (Value1) = $50
Final Value (Value2) = $70
Difference = $70 – $50 = $20
Proportional Change = $20 / $50 = 0.4
Percent of Change = 0.4 * 100 = 40%
In this case, the stock’s price experienced a 40% increase over one year.
2. Suppose you’re tracking your monthly website visitors, and over two consecutive months, the number goes from 5,000 to 3,000 visitors. To calculate the percent of change:
Initial Value (Value1) = 5,000
Final Value (Value2) = 3,000
Difference = 3,000 – 5,000 = -2,000
Proportional Change = -2,000 / 5,000 = -0.4
Percent of Change = -0.4 * 100 = -40%
In this example, the number of monthly website visitors decreased by 40%.
It’s important to remember that the percent of change can be positive or negative depending on whether the final value is higher or lower than the initial value. As you can see from these examples, the simple process of calculating percent of change can provide valuable insights into various trends and patterns in different contexts.