EXAMPLE 13 Population Tree Charts
Purpose: Demonstrate how to create a population tree chart with the axis in the middle.
Population tree charts (also known as, paired bar charts or sometimes tornado charts) are very useful when comparing two populations by age group.
Most savvy SAS/GRAPH programmers have found ways to create a basic population tree chart with a minimum of custom programming. For example, you might make the values for one population negative, to have them plot on the left side of the response axis. For a nice touch, you could create a user-defined format to make the negative response axis values look positive. A paper I co-authored with Dr. Moon W. Suh for the 1994 SouthEast SAS Users’ Group entitled “Creating Population ...