Playfair – an all-time Classic Chart

The aim of this tutorial is to show you some of the more advanced settings in GraPL, with the object of reproducing one of the all-time classics of econometric graphics. The chart we are going to build was first drawn in 1786 by William Playfair (“The Commercial and Political Atlas”, London), and was among the first recorded examples of statistical graphics. See Tufte “The Graphical Presentation of Quantitative Information” (page 65) for a splendid reproduction of the original chart. Here is what we can do in GraPL, with only a little ingenuity:

We will start by entering the data and letting GraPL take most of its default settings, with the addition of some simple headings and axis labels. Then we will explore some less common chart properties to get remarkably close to the spirit of the original.

Some of the challenges it sets us are easy, some are quite tricky to do well:

• the y-axis is at the right
• the ‘national debt’ is shown as a filled surface, for more immediate visual impact
• the axis units are written as a note, along the bottom of the chart
• the x-axis has tick-marks and gridlines at significant historic events
• the data-points are labelled (vertically) with a brief description of the event

Maybe you would like to take a moment to think which GraPL properties you would need to set to get some of these effects. Clearly the first stage is to enter the numbers, so let’s start by defining a new data sheet.

Continue to: Entering Some Data