1. Population Structure

2. Presentation Outline Introduction Proportionate age distributions
Population Pyramids
Sex Ratios
Demographic Pressure

3. Introduction
Age-structure of a population refers to size, age/sex composition and distribution of the population
Population structure reflects:
the long-term trends of fertility and mortality
Short-term impacts of war, migration and epidemics

4. Introduction (cnt’d)
The age structure of a population affects a nation’s key socio-economic issues e.g.
countries with young population would need to invest more in schools, create more jobs in future
Countries with high proportion of the aged (65+) need to invest more in health sector and social security

5. Key issues of a population structure
Proportionate age distributions
Population pyramid.
Sex ratios (males per 100 females) can also reflect a country’s population distribution
Dependency ratios

6. Proportionate Age Distributions
Refer to disaggregation of population characteristics by age
Proportionate age distribution can be calculated for:
Total population
Male population
Female population
Other characteristics include
education, occupation, marital status
religion, socio-economic status, ethnicity

7. Proportionate Age Distributions
Sex: Males and Females separately.
The total population
Marital status for persons 15+ (married, never married, widowed, divorced/separated)
ethnicity, for example African, European, mixed race, Asiatic, etc
Can be calculated for:

8. Female Population (15+ Yrs) by Age Group and Marital Status
Never Married
Married
Divorced/ separated
Widowed
Not Stated
Total
61.2
6.5
4.4
0.1
43.7
17.4
21.3
17.6
15.0
0.7
9.7
15.9
8.2
19.9
19.2
2.0
4.6
3.6
15.7
16.9
4.2
3.5
11.7
11.9
13.1
6.9
1.9
9.2
1.2
7.5
8.9
8.0
1.6
6.3
5.2
5.9
7.8
1.1
0.6
5.5
5.6
11.4
0.4
3.8
3.9
10.7
1.3
4.0
0.3
2.6
2.7
10.8
1.4
3.2
0.2
1.7
9.1
2.3
1.0
8.8
1.8
75 +
18.9 NS
23.6
100
Number
29 923
Source: ZIMSTAT, 2012

9. Male Population (15+ Years) by Age Group and Marital Status
Never
Married
Divorced/
separated
Widowed
Total
Number 15 - 19
95.2
1.9
0.2
2.7
100 20 24
71.7
26.3
1.3
0.1
0.7 25 29
31.5
64.9
3.0
0.3 30 34
12.5
82.7
3.9 35 39
6.2
88.4 40 44
4.2
89.6
3.8
2.2 45 49
3.6
89.0
3.4 50 54
88.6
3.7
4.5 55 59
2.1
3.1
5.0 60 64
2.0
88.3
6.5
96 779 65 69
1.7
86.9
8.2
73 055 70 74
1.8
84.1
2.9
10.9 10
62 230
75 +
77.0
2.8
18.0
0.4
96 640
Not
stated

10. Proportionate Age Distribution (cnt’d)
Apart from 5-year age groups, proportionate age distribution can be used for broad age groups such as:
child population (0-14 years),
Youth population (15-24), (15-34), etc
Women of child bearing age (15-49)
Economically active (15-64)
Elderly (65+ years)
etc

11. Population Pyramids
Distribution of a population by age and sex, using a 5 year interval.
Studies the age-sex structure of a country
Shows the effects of fertility, mortality and migration
Bars show the contribution of each age group

12. Population Pyramids Males are on left side Females on right side
Young persons at the bottom
The elderly are at the top

13. Population Pyramids The age groups can be divided into 3 categories:
Young Dependent (0-14 years)
Working Population (15-64 years)
Elderly Dependent (65+ years)
Percentages determine current reproductive status
Also point to the expected future
Shape reflects birth, deaths or migration patterns
Numbers or percentages can be used to show the distribution of the population

14. Comparing LEDC & MEDC

15. Types of Pyramids

16. Expansive Population Pyramids ( broad based)
Characteristics:
Has a young and growing population
Pyramid shaped
Broad base
Narrow top
Larger proportion of the population in younger age cohorts
Each age cohort is smaller than the one below it

17. Expansive Population Pyramids ( broad based)
Indicates:
high percentage of young population
High proportion of the dependent population
Rapid population growth due to high fertility
lower than average life expectancies
Expect low standard of living
High chances of overpopulation
Narrow top reflects high mortality
Typically representative of developing nations

18. Expansive Population Pyramids ( broad based)
Countries have to plan for:
Increased food production
Building more accommodation
Building more schools
Strengthened health care
more jobs in future
birth control campaigns

19. Population Pyramids
Source: ZIMSTAT, 2012

20. Developing Nation Pyramid: Kenya:

21. Constrictive Pyramid
Describe populations that are elderly and shrinking
Graphs tappers in at the bottom
Smaller percentage of the young population
Slow population growth

22. Constrictive Pyramid China Population Pyramid - 2017 Characteristics
High proportion of working population
Look like beehive
A moderate/ smaller proportion of young to old population
Typical of countries with high levels of social and economic development

23. China Population Pyramid (2017)

24. Stationary (Rectangular) Population Pyramid
***Indicates:
High survivorship
Low fertility
Stable structure, all age groups are equally abundant
tapers off toward the top

25. Stationary (Rectangular) Population Pyramid
Canada 2017
Characteristics
Zero population growth
Have a rectangular shape
Characteristic of developed nations
Overall quality of life is high

26. Stationary (Rectangular) Population Pyramid (cnt’d)
Implications
Plan for retirement packages
Proper health care services for the elderly
Plan for incentives for more births
Plan to hire foreign labour

27. What has happened in Qatar?

28. Sex Ratio = Number of males x 100
Sex ratios
-the proportional distribution of the sexes in a population aggregate, expressed as the number of males per 100 females
-The sex ratio is usually affected by fertility, mortality and migration
Sex Ratio = Number of males x 100
Number of females
Sex Ratio < 100 means more females
Sex Ratio > 100 means more males
Sex ratio at birth ranges between 104 and 110
It can be calculated for different age-groups

29. Sex ratios
Source: ZIMSTAT, 2012

30. Demographic Pressure There are three types of dependency ratios,
Child (0-14 years)
Elderly/ Old age (65 years and above)
Age dependency ratio (child and old age dependency combined).

31. (Elderly) Old Age Dependency Ratio
number of persons 65 years and above per 100 persons age years.
Measures the ratio of the aged to the potential working population.
A high ratio means those of working age have a greater burden in supporting the aging population.
The old age dependency ratio for the Zimbabwe in 2014 was 9 dependents per 100 persons in the age group years (LFCLF, 2014).

32. (Elderly) Old Age Dependency Ratio
Population age 65 years and above x 100
Population (15-64 years)

33. Child Dependency Ratio
Number of children under 15 years per 100 adults in the ages years.
It is used to measure the ratio of the young children to the potential working population.
This dependency ratio was 79 dependents per 100 persons in the age group years for Zimbabwe in 2014 (LFCLS, 2014).

34. Child Dependency Ratio
population under 15yrs x 100
population (Ages 15-64)

35. (Total) Age dependency ratio
It refers to the number of persons who are under 15 years of age plus persons 65 years and above, per 100 persons in the years age group.
This is used to measure the ratio of the young children and the aged to the potential working population.
When this dependency ratio is high, it shows that there is a high dependency burden for that particular population.
The age dependency ratio for Zimbabwe in 2014 was high, at 88 dependents per 100 persons in the age group years.

36. Calculation Number of Dependency (under 15 plus 65 and above) x 100
Working age population (15-64 years)

37. Effects of High Dependency Ratios
civil conflicts
poverty rates
Unemployment rates
Worsening natural resources shortages, e.g. water
Unmet need for family planning
NB: Balanced age structures increase the chances for peace and prosperity in the parts of the world that most need it.

38. Thank You