1. A.Janani
III yr MBBS

2. Contents
Introduction
Demographic cycle
Population trends
 World
 India
Demographic indicators
Vital events
Urbanization
Population explosion

3. Demos – population
Graphy – study
 It is the study of human population in a given
area during a given year.
 It focuses on 3 observable phenomenon
 changes in population size
 composition of population
 distribution of population in space
 Demographic processes
Introduction

4. Demographic cycle

7. Demography of India
 Second to China
 7th in land area-2.4% of world’s land
area
 16.87% world’s population
 1921- big divide
 Rate of population increase - 16 million
each year
 11th May 2000 – crossed 1 billion
 1.53 billion by 2050 – 10 billion

9. Demographic indicators
 Two parts:
 Population statistics
 Vital statistics
 Main sources: Censuses, National
Sample surveys, Registration of vital
events and ad hoc demographic studies

10. Population statistics
 Age and sex composition
 Age pyramid
 Sex ratio
 Dependency ratio
 Density of population

11. Age and sex composition
 0-14 years: 28.5%
 15-24 years: 18.1%
 25-54 years: 40.6%
 55-64 years: 5.8%
 65 years and over: 5.7%
 0-14 yrs male > females by 1.1% rural
areas(33.7%) , shows decline
 60+ female > male by 0.7%

12. Age pyramids

13. Sex ratio
 Number of females/ 1000 males, adverse to
women
 Differentials affecting sex ratio:
 Mortality conditions of males and females
 Sex selection migration
 Sex ratio at birth – affected by sex
selectivity at birth

15. Dependency ratio
 Persons above 65 yrs of age and children
below 15 yrs
 Total or societal dependency ratio=
Children 0 – 14 yrs + population >65yrs X 100
Population of 15 to 64yrs
 Crude ratio
 Total dependency ratio: 61.1%
 Young dependency ratio: 53.1%
 Old dependency ratio: 8.02%

16.  Demographic bonus: dependency ratio
declines because of decline in fertility, until it
starts to rise again because of longevity
 Demographic burden: used to indicate that
increase in total dependency ratio during any
period of time is mostly caused by increase
in old age dependency ratio
 Consequence of demographic transition
 Problem sooner or later

17. Density of population
 Important index of population
concentration
 Ratio between population and surface
area
 Indian census – number of persons
living per square kilometer
 345/ sq. km (2005)

19. Vital statistics
 Birth rates
 Death rates
 Growth rate
 Life expectancy
 Fertility rates

20. Birth rate
 20.97/ 1000 population
 Changes in government attitudes
towards growth
 Spread of education
 Increased availability of contraception
 Extension of services offered through
family planning
 Change in marriage pattern

21. Death rate
 7.4/1000 population
 Improvement in maternal and child
health services
 Implementation of expanded program on
immunization, diarrheal disease and
acute resp. infections

22. Growth rate
 Crude birth rate – crude death rate=
annual growth rate
 Control factors:
 Age distribution
 Marriage customs
 Cultural, social, economic factors
 India: 1.25%

23. Rating Annual rate of growth%
Stationary No growth
Slow growth <0.5
Moderate growth 0.5-1.0
Rapid growth 1.0-1.5
Very rapid growth 1.5-2.0
Explosive growth 2.0-2.5<

24. Family size
 Total number of children a woman has borne at
a given point of time
 Completed family size: total number of children
borne by a woman during her child bearing age
 Depends on factors like: duration of marriage,
education of couple, no. of live births and living
children, preference for male child, desired
family size etc.
 Net Reproductive rate = 2.6 (2008)
 Long term demographic goal – NRR = 1
 Two child norm

25. Literacy and Education
 Crude literacy rate =
no. of literates in the population X 100
total population
 Literacy rate - 74% ( male - 82% ;
female - 65.5% )
 Highest – Kerala (94%)
 Lowest – Bihar (49%)

27. Life expectancy
 Average number of years a person is
expected to live
 Male – 63 years ; Female – 64.2 years
 Highest – Japan (80 years)
 Least – Zambia (33 years)

28. Urbanization
 Number of persons residing in urban
localities
 Urban locality: towns having 5000 or more
inhabitants, density not less than 390/sq. km,
pronounced urban characteristics and at
least ¾ of adult male employed in pursuits
other than agriculture
 Urban population: 31.16% (2011)

29.  Increase in urban population due to:
 Natural growth
 Migration from rural areas

30. Population Explosion
 When the growth of the population is so
much that the natural resources are unable
to support and provide the basic needs.
 The world population is growing at a rate of
200 per min/ 10000 per hr.
 Reasons for population explosion:
 high birth rate
 low death rate

31.  Hazards:
 Physical
 Psychological
 Social
 Antisocial activities
 Miscellaneous

32. Thank you