iPhone growth is usually depicted in charts like the one on the above left. It looks impressive, but chartmeister Jason Snell argues that it underrepresents the true rate of growth …

Generally with graphs like this, the creator picks a convenient format and then scales the numbers to fit. That can, however, sometimes create a very misleading impression.

A classic problem — sometimes inadvertent, sometimes deliberate — is when trying to make small changes legible.

Let’s say that a percentage has changed in the 90%-95% range over a number of years. Typically, the Y axis will show something like the 85% to 100% range rather than the full 0% to 100%. That helps make the changes clearer, but it also makes them look much larger than they are. You can see a whole bunch of examples of this here.

But with iPhone sales, we have the opposite problem. To show them alongside Mac and iPad sales, and trying to get graphs in the same format, you have to significantly compress the Y scale. Typically, then, you’ll end up with a graph that looks something like the one on the left, above.

If, however, you use the same Y axis as you do for Mac sales, you get a very different perspective: the graph on the right. Here’s what Jason Snell says about it:

Check out a legible version of the right-hand iPhone growth chart, as well as comparative graphs, over at Six Colors.

If charts don’t always clearly portray just how much Apple’s business has grown over the decade, they really obscure just how huge the iPhone is compared to Apple’s businesses. I try to get it across in other chart types, but these historical revenue charts never do it justice because the scale of the charts doesn’t match.

So this time, I thought I’d match the scales. The Mac and iPad charts above are both at the same scale. Below I’ll leave the iPhone revenue chart for the decade, at the same scale as the Mac and iPad.