What is 'Percentage Change'
Percentage change is a simple mathematical concept that represents the degree of change over time. It is used for many purposes in finance, often to represent the price change of a security.
BREAKING DOWN 'Percentage Change'
Percentage change can be applied to any quantity that you measure over time. Let's say you are tracking the quoted price of a security. If the price increased, use the formula [(New Price  Old Price)/Old Price] and then multiply that number by 100. If the price decreased, use the formula [(Old Price  New Price)/Old Price] and multiply that number by 100.
This formula is used both to track the prices of individual securities and of large market indexes, as well as comparing the values of different currencies. Balance sheets with comparative financial statements will generally include the prices of specific assets at different points in time along with the percentage changes over the accompanying periods of time.
Calculating Percentage Change StepbyStep
To calculate a percentage increase, first work out the difference (increase) between the two numbers you are comparing:
Increase = New Number  Original Number
Next, divide the increase by the original number and multiply the answer by 100:
% increase = Increase ÷ Original Number × 100.
If the answer is a negative number, that means the percentage change is a decrease.
To calculate percentage decrease:
First, work out the difference (decrease) between the two numbers you are comparing.
Decrease = Original Number  New Number
Next, divide the decrease by the original number and multiply the answer by 100.
% Decrease = Decrease ÷ Original Number × 100
If the answer is a negative number, this is a percentage increase.
If you wish to calculate the percentage increase or decrease of several numbers, it's best to use the formula for calculating percentage increase. Positive values indicate a percentage increase whereas negative values indicate percentage decrease.
Example of Calculating Percentage Change
As an example of calculating percentage change in a reallife scenario, consider Bob, who worked a total of 35 hours in January. In February, he worked 45.5 hours, by what percentage did Bob’s working hours increase in February?
To solve this calculation, first calculate the difference in hours between the new and old numbers. 45.5  35 hours = 10.5 hours more hours worked by Bob in February. To work out the increase as a percentage, divide the increase by the original (January) number:
10.5 ÷ 35 = 0.3
Finally, to get the percentage we multiply the answer by 100. This simply means moving the decimal place two columns to the right.
0.3 × 100 = 30
Therefore, Bob worked 30 percent more hours in February than he did in January.

Absolute Percentage Growth
Absolute percentage growth is an increase in the value of an ... 
Negative Growth
Negative growth is a contraction in a country's economy as evidenced ... 
Average Return
The simple mathematical average of a series of returns generated ... 
Aggregate Hours
Aggregate hours refer to the total sum of hours worked by all ... 
Value Change
Value change is an adjustment to a stock's price to reflect the ... 
Basis Point (BPS)
Basis point (BPS) refers to a common unit of measure for interest ...

Investing
Why Your Investment Growth Calculator May Be Wrong
Many simple investment growth calculators fall short, so here's one you should use instead. 
Retirement
The 3 Best Social Security Calculators For 2016
Find out how to analyze your Social Security benefits under different retirement scenarios using multifunctional online Social Security calculators. 
Personal Finance
Schedule Loan Repayments With Excel Formulas
Learn how to calculate all the particulars of a loan using Excel, and find out how to set up a schedule of repayment for a mortgage or any other loan. 
Investing
The Art Of Selling A Losing Position
Knowing whether to sell or to hold is tough. And no rule fits all. Find out what to consider. 
Trading
Sensitivity Analysis For BlackScholes Pricing Model
Trading options requires complex calculations, based on multiple parameters. Which factors impact option prices the most? 
Personal Finance
5 Financial Math Skills Every Teen Should Learn
Calculus is good for abstract thinking, but what math skills should every student learn for managing his or her money? 
Investing
How to calculate your investment return
How much are your investments actually returning? The method of calculation can make a significant difference in your true rate of return. 
Retirement
How Working After Retirement Affects Social Security
Working after retirement can positively affect your Social Security benefits.

How do you calculate the percentage gain or loss on an investment?
Calculating the percentage gain of an investment is quite easy. Here is what you need to know to determine the gain or loss. Read Answer >> 
Calculate the profit and loss of your portfolio
Finding the total percentage gain or loss on a portfolio requires simple calculations, but first, you should understand how ... Read Answer >> 
How do I calculate compound interest using Excel?
Learn how to calculate compound interest using three different techniques in Microsoft Excel. Read Answer >>