Setting up the X-axis

The only really tough challenge is to get those irregular ticks and grid-lines (try this in Excel some day!). GraPL treats the tick-mark settings in one of 3 ways, depending on how many numbers you provide:

1. A single number (e.g. X-tick=5) sets the tick-marks every n units, so in the example we could have ticks every 50 years by setting X-tick=50. To try this, open up the tree of properties under Axes,X-axis and change the value from (auto) to 50. Press Enter to see the effect.
2. A pair of numbers sets the major ticks every n units, and draws m minor ticks in each gap. For example you could set X-tick=20,3 to have big ticks every 20 years with minor ticks every 5 years. Try it!

Still not what we need! If you give GraPL more than two numbers, it assumes you know exactly what you want and just draws tickmarks where you tell it. This is now very easy, as we just want the ticks at all the x-values, which are listed in the ‘Year’ column of our data-sheet. Set X-tick to ‘Year’ and add ‘Grid’ to the X-axis style (use the ‘...’ button if you are unsure of the right magic words) for the final cut at our X-axis:

This is definitely converging on what we want. Now to sort out the Y-axis and some headings.

Continue to: Setting the Y-axis and Margins