A population pyramid is a type of chart used in demographics to show a distribution of a population by age and gender at some point in time.
In this representation, age groups are set as points (points on an axis), males and females are set as series (differently colored items of a legend), while time and other parameters are set as filters (one particular time point is selected instead of selecting a time range). At that, males and females are shown as bars on opposite sides of zero.
An example of such chart is shown below.
Below are steps how to create a pyramid chart at knoema.com.
1. Create a new dashboard.
2. Add a new chart gadget by clicking a “Chart” icon.
3. Select a dataset which contains data by age and gender. In this example, we use the dataset LFS by sex and age from OECD.
4. Go to “Customize” mode by clicking a “gear” icon.
5. Select a country and set it as a filter by clicking “F” in blue square.
6. Select one gender (for example, male) and set it as series by clicking “S” in blue square.
7. Add the other gender (female) with negative values by adding a calculation “0 - female” using "Add calculation" button.
8. Select age groups and set “Age” dimension as “Points”.
9. Select an individual time member and set “Time” dimension as a filter.
10. Make a selection in remaining dimensions and set them as filters.
11. Go to “Appearance” tab and put both males and females on the primary axis by clicking “Primary” button at “Series” section.
12. In “General” section switch to “Pyramid” type of chart.
All set, pyramid chart is created! After that, you can adjust its appearance as follows.
1. Add a legend in “Plot area” section.
2. Adjust colors of genders in “Series” section.
3. Adjust title and subtitle. You can use automatic elements in curly brackets.
4. Add a footnote by clicking “Footnote” button in the “General” section. You can use an automatic footnote to show a link to a dataset used.
Finally, save your gadget by clicking “Save” button.
Also, you can parametrize your gadget so that a user who views a dashboard can change a country or other available parameter which is shown on a chart.
1. Click “Parametrize” button.
2. Click a gadget that you want to parametrize and select parameters by which you want to parametrize the gadget. Click “Apply” button so save parametrization.
3. Now you can switch between parameters in drop-down lists at the top of a dashboard and they will be applied to the gadget on the flight. At that, a title/subtitle of the gadget will be also automatically adjusted if you used automatic elements in curly brackets.
4. You can add titles of drop-down boxes by clicking their names in parametrization editing mode.
On a pyramid chart, you can show absolute values as well as percentage distribution. To show percentage distribution on a pyramid, do the following steps.
1. Edit an existing pyramid chart by clicking “Edit” in its menu.
2. Go to “Age” dimension and clear the selection by clicking “Clear” button.
3. Add a calculation of a share of a total “[X]/Total*100”. In this calculation [X] is an automatic element which will be replaced with corresponding age groups on the next step.
4. Click “Save” button and select age groups which you want to use instead of [X] in the formula and click “Ok”.
5. As a result, you will see that all age groups were added to the left panel in the “Age” dimension. Save the gadget by clicking “Save” button.
Done. Now the pyramid shows percentage distribution instead of absolute values in persons.
You can adjust the subtitle of the pyramid in-place to read “Percentage distribution”, for example.
Finally, give the title to your dashboard and save it by clicking “Save” button.
As a result, you will get the following dashboard with pyramid chart and the possibility to change the country and indicator.