Tuesday, September 8, 2009

Percents, perhaps

This may seem hard to believe, but I have often had to explain to journalists, both seasoned and newcomers, how to compute a simple percent change between one number and another. I'm talking eighth or ninth grade math here. Blame for this ignorance can be shared by many: our education system, the explosion of calculators, the computer revolution, whatever. Anyway, the math is simple: You divide the later figure by the earlier figure and subtract 1. But you don't need to remember that. Just follow these few steps, using Excel or any other good spreadsheet.

First, of course, get the numbers. Say a small nonprofit organization issues a statement that it has taken in $354,600 in donations in 2009, versus $329,089 the year before. By what percent has the organization increased its fundraising?

Open the spreadsheet. In the first "cell," that is, A1, type in the year "2009."
1) Tab over to the second cell, or B1. Type in the year "2008."
2) Tab over to C1. Type in "Percent change."
3) Now tab back to A2 (which is just under A1). Type in $354,600.
4) Tab over to B2. Type in $329,089.

5) Now tab over to C2. Here's where the computing starts: In C2, type this formula: =A2/B2-1.
6) You get 077522. That doesn't look like a percent, but it is. It's 7.8 percent. You can see that yourself by putting a decimal point after the 07. But here's an easier way (well, a more computer-savvy way):

7) Select the C2 cell, and search the formatting bar for the percent (%) sign. Click it. You'll see the C2 cell change to 8%. That's your answer, rounded. The organization increased its fundraising revenue by around 8 percent.
8) If you want a more precise figure, click on the "Increase decimal" icon on the formatting bar(near the % icon). That will change the 8% to 7.8%. Done.


ArthurZ said...

Nathan, thanks for reminding me that Excel is a great tool. Instead of wasting paper scratching out equations, why not just use Excel? It's all there....

Nathan said...

Great. Incidentally, hope you had a good time on your camping trip. We'll see you soon.