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POPULATION PYRAMIDS. Objectives. WHAT is a population pyramid? HOW to read a population pyramid? Recognise SHAPES of population pyramids. IMPORTANCE of population pyramids. What is a population pyramid?.
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Objectives • WHAT is a population pyramid? • HOW to read a population pyramid? • Recognise SHAPESof population pyramids. • IMPORTANCE of population pyramids.
What is a population pyramid? • It is a diagram that gives information about the proportion of males and females in each age group. • Also shows: - proportion of young people (0 -14 ) - proportion of working people (15 – 59) - proportion of elderly people (60+) Each age-group designation is called a COHORT
What is a population pyramid? Vertical Axis - Age Groups Elderly dependents Working population Young dependents Horizontal Axis – Percentage / number
How to read a population pyramid? • Read the title e.g. country or city or racial group • Comment on general shape of the pyramid • Note the proportion of people in various age groups (cohorts) • Note the sex ratio • Interpret the data
Types of Population Pyramid 1. Triangular-shaped 2. Beehive-shaped Pyramid 3. Rectangular-shaped Pyramid Shape of pyramids is controlled by • Births (but mostly CBR!) • deaths, & • migrations.
Broad-based Pyramid Title: India, 2000 Shape: Broad Base - high birth rates Narrow Top - small elderly pop - high death rate Proportion: - Large proportion of young - high young dependency ratio Sex Ratio: Balance pyramid - Balance sex ratio
STOP • Where is India on the Demographic Transition Model?
Indonesia 2000 Malaysia 2000
Beehive-shaped Pyramid Title: Singapore, 2000 Shape: Rocket-shaped / Narrow Base – Low Birth Rates, Slow pop growth Proportion: Large proportion of working population, 15-59 yr old - large group of economically active pop Sex Ratio: Balanced pyramid
Hong Kong 2000 Taiwan 2000
STOP • Where are Beehive shaped pyramids on the Demographic Transition Model?
Rectangular Pyramid Title: Netherlands, 2000 Shape: Rectangular-shaped - Zero Pop Growth Narrow Base - Low Birth Rates - Life-expectancy is high e.g. 80+ - Low death rates Proportion: Bars of equal length - Balance Proportion Sex Ratio: Balance pyramid - Balance Sex Ratio
UK 2000 Netherlands 2000
STOP • Where are Rectangular Based Pyramids on the Demographic Transition Model?
Population Structure and Composition • Population pyramids…show age and gender groups. How do MDC’s and LDC’s differ? • 1.) Sex Ratio: # of males per 100 females. In general slightly more males born, but women outlive men • Eur and NA 95 males: 100 females • World wide 102 males: 100 females
Pop Structure and Composition – cont’d. • 2.) Age Distribution • Dependency Ratio: # of people too old or young to work, compared to # of people in productive yrs. • % of pop under 15 = % over 65 divided by % in between 15-65 multiplied by 100 • Tells you how many dependents for every 100 workers • Stage 2 countries: ratio is 1:1 (1 worker for every dependent) Dependents are young • Stage 4 countries ratio is 2:1 (2 workers for every dependent) Dependents are young and old
Age Distribution – cont’d • Graying of the pop in MDCs – more than ¼ of all govn’t expenditures in US, Canada, Japan, and W. Eur goes to Social Security, health care, and other programs for the elderly • Baby Boomer Cohort in US (born 1946-1964)…what does this mean for you? • Generation X = 1965-1980
Importance of Population Pyramids • Policy Planning ~ future housing estates ~ future schools ~ future jobs • Comparison with other countries ~ developed (US) vs developing (India)