[This article was first published on free range statistics - R, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here)Want to share your content on R-bloggers? click here if you have a blog, or here if you don't.I came across a chart of long term real gross domestic product per capita for Australia (1900 to about 2020) that had a couple of mistakes in its y axis scale and labelling. I wanted to see for myself what it should actually look like.Looking for data for this drew my attention to the excellent Maddison Project, which publishes long term estimates of real GDP per capita, in 2011 prices, for many countries. It’s certainly not perfect (price comparisons over such a long period of time—and they go well back before 1900—is a vexed business!), but it looks like a great effort. It’s necessary to have something like this from the economic historians because most standard official statistics series for Australia only go back to 1959, due to the complications of comparisons over time.The Maddison Project’s latest release is 2023.Here’s my re-creation of the original chart (which is not shown here), but with correct y axis labels:A distinctive feature of this chart is that it compares the actual growth trajectory to a constant rate of growth from 1900 to present. It’s a nice comparison. It takes care to draw—it’s definitely not the same as a line of best fit. On a logarithmic scale where the constant growth is a straight line, it gives a good point of reference for the faster and slower periods of growth.Here’s my code that draws the chart. The work is actually done by a project-specific function draw_chart(), which draws a fairly decent chart for any given country available in the database. This lets me easily produce similar charts for other countries (results shown after the R code).# download latest version of Maddison data from:# https://www.rug.nl/ggdc/historicaldevelopment/maddison/releases/maddison-project-database-2023library(tidyverse)library(readxl)library(scales)library(glue)library(countrycode)gdppc