Population Pyramid

Introduction

A population pyramid, also called an age pyramid or age picture diagram, is a graphical illustration that shows the distribution of various age groups in a population (typically that of a country or region of the world), which forms the shape of a pyramid when the population is growing. A population pyramid is also used in ecology to determine the overall age distribution of a population; an indication of the reproductive capabilities and likelihood of the continuation of a species.

It typically consists of two back-to-back bar graphs, with the population plotted on the X-axis (↔) and age on the Y-axis (↑) , one showing the number of males and one showing females in a particular population in five-year age groups (also called cohorts or bands). Males are conventionally shown on the left and females on the right, and they may be measured by raw number or as a percentage of the total population.

Inputs

To show the Population Pyramid in use, we will model the 2011 population within the Blacktown LGA in NSW, and compare how they are likely to change over time.

  • Select Blacktown LGA as your area
  • Select LGA Small Area Population Projections 2006-2031 for Australia as your dataset, making sure you choose 2011 as your filter year.

We now want to open the Population Pyramid chart (ToolsChartsPopulation Pyramid). Enter your parameters as shown below (the meanings of all these inputs are explained below), and click Add and Run.

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[Click to Enlarge]

  • Dataset Input: This is the population dataset that you would like to create a population pyramid for. In this instance, we are using the LGA Small Area Population Projections 2006-2031 for Australia, for Blacktown in 2011
  • Males Variables or Column Names: This is where you select all of the different male cohorts to be shown on the left hand side of the pyramid. In this instance, it will be all of the columns named Males[X]to[Y]
  • Females Variables or Column Names: This is where you select all of the different female cohorts to be shown on the right hand side of the pyramid. In this instance, it will be all of the columns named Females[X]to[Y]
  • Chart Title: This is where you specify a title for your chart. In this Instance we have named it 2011 Population Pyramid in Blacktown LGA
  • Age Interval:  This is where you specify the size of the age bands. In this instance, we have grouped the population into 5 year age groups
  • Grid: This is where you specify whether or not you want to have a grid on your population pyramid
  • Greyscale: This is where you specify whether or not you want your graph to be in colour or black and white/grey

Outputs

Once your tool has run, click on the Display button to display the population pyramid. It should look something like the image below.

[Click to Enlarge]

[Click to Enlarge]