Calculating Delta Percentage

Published
<h3>Calculating Delta Percentage</h3>

Sometimes you report a change as an absolute change, such as the Dow Jones dropping by 44.05 points. Other times you report a percentage change, such as the Dow Jones dropping by 0.26 percent. The percentage change shows how big the change is relative to the initial value. The word “delta” comes from the Greek letter delta, which is represented as a triangle and is commonly used to symbolize a change. Delta X, or the change in X, is equivalent to X(final) – X(initial). You can calculate the percentage change in X in two ways.

Method 1

Step 1

Calculate the percentage change using the equation [X(final) – X(initial)] / X(initial) * 100.

Step 2

Suppose the cargo space is 34.2 in the old model of a car and 32.6 cubic feet in the new model. Subtract the new value from the old value. 32.6 cubic feet – 34.2 cubic feet = -1.6 cubic feet.



Step 3

Divide by the old value: -1.6 cubic feet / 34.2 cubic feet = -0.0468.

Step 4

Convert to a percent: -0.0468 * 100 = -4.68 percent. The cargo space dropped by 4.68 percent.

Method 2

Step 1

Calculate the percentage change using the equation [X(final) / X(initial) * 100] – 100 percent.

Step 2

Use the same cargo space example of 34.2 in the old model of a car and 32.6 cubic feet in the new model. Divide the new value by the old value: 32.6 cubic feet / 34.2 cubic feet = 0.953.



Step 3

Convert to a percentage: 0.953 * 100 = 95.3 percent.

Step 4

Subtract 100 percent. 95.3 percent – 100 percent = -4.7 percent. The difference between Method 1 and Method 2 comes from the difference in rounding.

Dave Pennells

By Dave Pennells

Dave Pennells, MS, has contributed his expertise as a career consultant and training specialist across various fields for over 15 years. At City University of Seattle, he offers personal career counseling and conducts workshops focused on practical job search techniques, resume creation, and interview skills. With a Master of Science in Counseling, Pennells specializes in career consulting, conducting career assessments, guiding career transitions, and providing outplacement services. Her professional experience spans multiple sectors, including banking, retail, airlines, non-profit organizations, and the aerospace industry. Additionally, since 2001, he has been actively involved with the Career Development Association of Australia.