1. The Demographic Transition
April Buzby Keene State College 2009
The Demographic Transition
Keene State College
Human Cultural Mosaic
ISGEOG203 Fall ‘09
Professor: Dr. Rydant
Created by: April Buzby
Supplemental Instructor

2. April Buzby Keene State College 2009
Introduction
Demographic Transition Model (DTM)
Represents a nation’s transition through industrialization
Commonly involves 4 stages
An idealized picture of population change in a country.
April Buzby Keene State College Fall 2009

3. Introduction Population Pyramid
Shows the distribution population by age and sex
A specific age group (i.e. ages 0-4) is called a cohort.
Different stages in the demographic transition show considerably different population pyramids
April Buzby Keene State College Fall 2009

4. Stage 1: Pre-Industrial Period
Crude Birth Rate: High
Crude Death Rate: High
Rate of Natural Increase: Fluctuating
Examples: Britain in the 17th and 18th century; some remote Amazon tribes
April Buzby Keene State College Fall 2009

5. Stage 1: Birth Rate Birth Rate is high due to: Lack of family planning
High Infant Mortality Rate
Need for workers in agriculture
Religious beliefs
Children as economic assets
April Buzby Keene State College Fall 2009

6. Stage 1: Death Rate Death Rate is high due to: Disease Famine
Lack of clean water and sanitation
Lack of health care
War
Limited food supply
Lack of education
April Buzby Keene State College Fall 2009

7. Stage 1: Population Change
Due to high birth and death rates, population is stable.
Population Growth Rate: ≤ 1%
Doubling Time: ~100 years
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8. Stage 1: Age Structure Population Pyramid Shape: Concave triangular
Age Structure of Population:
Rapid fall in each age group due to high death rates
Short life expectancy
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9. Stage 2: Transitional Period
Crude Birth Rate: High
Crude Death Rate: Decreasing
Rate of Natural Increase: Increasing
Examples: Britain late 18th Century to mid-19th Century, Kenya
April Buzby Keene State College Fall 2009

10. Stage 2: Birth Rate Birth Rate remains high due to:
Total Fertility Rate (TFR): 4.56
People are used to having many children. Takes time for culture to change
Religious beliefs
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11. Stage 2: Death Rate Death Rate decreasing due to: Improved hygiene
Improved sanitation
Improved food production and storage
Improved transport for food
April Buzby Keene State College Fall 2009

12. Stage 2: Population Change
“Population Explosion" - gap between deaths and births grows wider.
England’s Agricultural and Industrial Revolutions.
LDC cause of today’s population explosion
Population Growth rate: 3%
Doubling Time: years
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13. Stage 2: Age Structure Population Pyramid Shape: Triangular
Age structure of Population:
Growing young dependant population
Increasingly youthful age structure
Accelerating population growth
April Buzby Keene State College Fall 2009

14. Stage 3: Industrial Period
Crude Birth Rate: Decreasing
Crude Death Rate: Continues to decrease
Rate of Natural Increase: Increasing but at a slower rate
Examples: Britain early 20th century; Brazil; Mexico
April Buzby Keene State College Fall 2009

15. Stage 3: Birth Rate Birth Rate decreasing due to: TFR: 2.05
Improvements in contraceptive technology.
Changes in values about children and sex.
Parents need fewer children.
Rising costs of dependent children to a family.
Valuation of women beyond motherhood.
Working women have less time to devote to child rearing.
April Buzby Keene State College Fall 2009

16. Stage 3: Death Rate Death Rate low due to: Better Health Care
Vaccinations
Better understanding of the spread of diseases
Pre-natal care
Improved sanitation (i.e. indoor plumbing)
Improved quality and quantity of food
April Buzby Keene State College Fall 2009

17. Stage 3: Population Change
Large cohort equals continued population growth
Population Growth rate: ≤ 1%
Doubling Time: 65 years
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18. Stage 3: Age Structure Population Pyramid Shape: Columnar
Age structure of Population:
Decreasing TFR
Bulge in the reproductive cohorts
Narrowing pyramid base
April Buzby Keene State College Fall 2009

19. Stage 4: Post-Industrial Period
Crude Birth Rate: Low
Crude Death Rate: Low
Rate of Natural Increase: Stable
Examples: Britain late-20th century; Sweden; Japan
April Buzby Keene State College Fall 2009

20. Stage 4: Birth Rate Birth Rate low due to: TFR: 2.1 Family planning
Good health
Improved status of women
Later marriages
April Buzby Keene State College Fall 2009

21. Stage 4: Death Rate Death Rate low due to: Improved health care
High quantity and quality of food supply
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22. Stage 4: Population Change
TFR falls to replacement fertility levels (2.1)
Zero Population Growth (ZPG) reached
Stable but high population size
Population Growth rate: >1%
Doubling Time: ~1000 years
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23. Stage 4: Age Structure Population Pyramid Shape: Inverted
Age structure of Population:
Characterized by stability.
Age structure becomes older.
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24. A Fifth Stage?
The original Demographic Transition Model has just four stages; however in some cases the fertility rate falls well below replacement level and population decline sets in rapidly. It is theorized that a fifth stage is necessary to account for this demographic stage.
Example: Romania
CBR: 10.53
CDR: 11.88
TFR: 1.39
Population Growth : %
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25. Modern Applicability Generalization from European experience
Assumes that population changes are induced by industrial changes and increased wealth
Assumes that the birth rate is independent of the death rate.
Assumes that countries will go through all the stages.
Some countries may skip stages.
Does not account for migration.
Does not take into account the role of social change in determining birth rates, e.g., the education of women.
Some countries are in a demographic trap and can not progress
April Buzby Keene State College Fall 2009

26. The Human Development Index and the DTM
Fertility declines at low and medium Human Development Index (HDI) levels
Theorizes that advanced HDI promotes a rebound in fertility.
In many countries with very high levels of development (around 0.95) fertility rates are now approaching two children per woman.
Example: Netherlands
CBR: 12
CDR: 9
TFR: 1.7
Population Growth : 0.7
HDI: (9th)
April Buzby Keene State College Fall 2009

27. Conclusion Represents a nation’s transition through industrialization
Commonly involves 4 stages
An idealized picture of population change in a country.
Used to indicate future birth rates, death rates , and the population size of developing countries
Generalization from European experience
Assumes that population changes are induced by industrial changes and increased wealth
Different stages in the demographic transition show considerably different population pyramids
April Buzby Keene State College Fall 2009

28. Glossary
Crude Birth Rate (CBR): the annual number of live births per 1000 people.
Crude Death Rate (CDR): the annual number of deaths per 1000 people.
Total Fertility Rate (TFR): the annual number of live births per woman from age 15 to 49 years old.
Infant Mortality Rate: the annual number of deaths of children less than 1 year old per 1000 live births.
Life Expectancy: number of years which an individual at a given age could expect to live at present mortality levels.
Rate of Natural Increase: the difference between the number of live births and the number of deaths during the year found through the equation birth rate (b) – death rate (d) = rate of natural increase (r).
Doubling Time: the number of years it will take to double the present population given its current rate of population growth.
Replacement Fertility: the level of fertility at which a cohort of women on the average are having only enough children to replace themselves and their partner in the population.
Population Momentum: the tendency of population growth to continue after the TFR achieves replacement fertility levels.
April Buzby Keene State College Fall 2009

29. Sources CIA World Factbook
Domosh , M., Neumann, R.P., Price, P.L., Jodan-Bychkov, T.G., (2009). The human mosaic, eleventh edition.
Montgomery, Keith. The demographic transition
Myrskyla, M., Kohler, H-P., and Billari, F. Advances in development reverse fertility declines. Nature 460, (6 August 2009).
U.S. Census Bureau, Population Division. International Data Base (IDB).
United Nations Development Programme (UNDP). Human Development Reports.
April Buzby Keene State College Fall 2009