Age Pyramid

1. Understanding Age-Sex Structure of
Populations
Dr T R Dilip,
International Institute for Population Sciences
Course C1: Introduction to Demography and History of Population
MBD/MA/MSc/MPS
1st October 2021

2. Age composition
• Functional relationship between age composition and
components of population change (fertility, mortality &
migration)
• Age distribution of population has a significant socio-
economic consequences
– Labor force
– Educational and Health Planning
– Other social security schemes needed
– Level of consumption
• Measured using % <15 years & %>60 years,
Dependency Ratio, Child Woman Ratio, Mean &
Median Age & POPULATION PYRAMID

3. Population Pyramid
• displays a population’s age and sex composition
• Horizontal bars present the numbers or proportions of
males and females in each age group
• Separate for males & females because:
– Mortality experiences males and females are different in any
population and warrant separate consideration
– Fertility is restricted to particular age group (15-49 years)
– Migratory behavior too varies between males and females
• Demographic process cannot be interpreted unless the
age sex structure are considered simultaneously

4. Age or Population Pyramid
• displays a population’s age and sex composition
• Horizontal bars present the numbers or proportions of males and
females in each age group
• Word “pyramid” due to conical shape
• An important means to trace demographic history of a population
• Abnormalities will be reflected in the pyramid through a depression
or protrusion
• Abnormalities include war, natural calamities, baby boom,
economic prosperity or depression
• Age pyramid can be used to check quality of age data under/over
enumeration of certain ages or sex or age misreporting (HENCE
SOME CAUTION BEFORE PREPARING PYRAMID)

5. Population Pyramid: Shape1, rapid population growth (Eg. Nigeria)
• Those
depicting
rapid growth
high birth
rate lower
death rate
(Real
Pyramid)

6. Population Shape 1
• Really looks like a pyramid
• each age cohort is larger than the one born before it
• shape results primarily from sustained high fertility
• pyramid shape also results from declines in mortality
• High mortality in the past, older age groups occupy a
small section of the pyramid.
• Base is broadened by the fact that mortality,
particularly infant mortality, is declining

7. Population Pyramid: Shape 2, Slow population growth (eg: Bangladesh)
• Those
exper
iencin
g low
birth
rate
lower
death
rate .
Annu
al
rate
of
chang
e 1%

8. Population Pyramid: Shape 3, population decline (eg: Japan)
Those
depicting
populatio
n decline.
Annual
rate of
change
-0.3%

9. Tracing Demographic History Using
Population Pyramid
Population pyramids that are constructed by
single years of age can illuminate reasons for a
population’s age structure that larger age
categories might mask.

11. Population Pyramid of Japan 1995

12. Population Pyramid 2019 (World & India)
(% of male & female population based)

13. Population Pyramid 2019 (World & India)
(number of male & female population based)
World India

15. Population Pyramid in Low and High Income Countries
High Income Countries Low Income Countries

16. South Asia
Europe and North America
Sub-Saharan Africa

17. Source: Report_Population_Projection_2019.pdf (nhm.gov.in)

18. Source: Report_Population_Projection_2019.pdf (nhm.gov.in)

21. View this presentation before the next class
Kulkarni P. M. Demographic Transition in India:
https://censusindia.gov.in/digitallibrary/Demogr
aphic-Transition-in-India.pdf

22. Resources used
• Kulkarni P. M. Demographic Transition in India:
https://censusindia.gov.in/digitallibrary/Demographic-Transition-in-India.pdf
• Haupt, A., Kane, T.T. and Haub, C., 2011. PRB's population handbook.
https://users.pop.umn.edu/~rmccaa/3797/prbhbook.pdf
• “Population: A Lively Introduction, 5th Edition,” Population Bulletin 62, no. 1
(Washington, DC: Population Reference Bureau, 2007 https://www.prb.org/wp-
content/uploads/2007/03/62.1LivelyIntroduction.pdf
• Ramkumar, R. and Gopal Y S , 1986. : Technical Demography. New Delhi: Wiley
Eastern Limited.
• National Commission on Population. 2019., Report of The Technical Group on
Population Projections, Mew Delhi: MOHFW
Report_Population_Projection_2019.pdf (nhm.gov.in)
• United Nations, Department of Economic and Social Affairs, World Population
Prospects (country Profiles) https://population.un.org/wpp/Graphs/

23. Thank You