Joe Grimm, Recruiting and Development Editor of the Detroit Free Press, tells you how to get the percentage change. These cheat sheets together with the Powerpoint presentation Newspaper math can help you become more diligent with digits.

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Figuring percentage change

Percentage means per hundred

So, a percentage is really just a fraction – something out of a hundred.

To get the percentage change, divide the difference between the two numbers by the starting number.

  • Percentage increase

    Divide the change by the number you started with. An increase from 50 to 75 works like this:

25/50 = .50 = 50% increase

  • Percentage decrease

We do this the same way, but we call it a decrease. A decrease from 75 to 50 works like this:

25/75 = .33 = 33% decrease

  •  Multiplying by percentage

    To figure or check the percentage of something, first estimate so that you can later check to see if you’re in the ballpark.

    Then it’s just multiplication.

    A 30 percent increase in a number would be 1.30 (or 1.3) times the original number. For example, a 30 percent increase on $85,000 would be $110,500.

    A 23 percent decrease in something would be .77 times the original number. For example, a 23 percent decrease in $85,000 would leave you with $66,450.

    In some stories, the amount of the change, rather than the new total, may be most relevant. Then, using the first example above, you would say that the 30 percent increase on the $85,000 amount brought an increase of $25,500. It is never wrong to give all the numbers: first, last and the amount of change.

  • Helpful web sites

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