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If you make a lot of charts, here’s a too often unused feature in Excel: Logarithmic Scale.
Thanks to fellow Excel Badass Blogger Michael Rempel for this tip! In the video below, I take the tip further to include a secondary axis and and area graph.

Let’s jump right in …

PROBLEM:

There’s a wide range between your data points. You need to make a graph, but the wide range makes the small numbers invisible.

The examples in the table below would make for useless visuals if you place them in an out-of-the-can column, line or area graph.

Metric# of EntriesLowest ValueHighest Value
Population40 Cities1103.47M
Donations45 Donations\$2\$1,500
Product Weights 20 Products0.02 lbs370 lbs
February Walk-in Customers30 Salons5 visits209 visits
Q1 Sales Revenue40 Sales Reps\$0\$310,480

This graph shows donations and is useless for any meaningful analysis. Under \$200, we’re in the WTF? zone. (This might be fine as a snapshot or very high level overview but that’s about all.)

We can’t tell that Wally donated \$2 and Cat donated \$71. But let’s not pull out the magnifying glass.

In the chart below, we use a logarithmic scale and the chart adjusts, making the smaller numbers visible. There is a deeper explanation about logarithms, and Wikipedia can explain more than you want to know. For our purposes, we need to know that there is a solution for crazy graphs that have nearly invisible data.

What can we see now? Wally’s donation is much less than \$10; in fact, very few donors are in the  sub-\$10 range, and Cat is not quite at \$100.

SOLUTION  The video below shows how to make logarithmic charts, and we take the sanity even further with combo charts and secondary axes.

That’s it for today. Now, I urge you: keep your data clean and do not make crazy visuals.

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magnifying glass photo credit: Mike “Dakinewavamon” Kline via photopin cc