Stem and leaf plot

http://mainland.cctt.org/mathsummer/JosephBond/StemAndPlots/stem-and-leaf_std.htm

This is a stem and leaf plot. It is a quantitative way of representing data. It uses a number group such as tens hundreds thousands and so forth and maps out how many numbers occur in each group of numbers. In this plot this is a plot of per capita GNP of western Africa.