Population Pyramids

1. Population Pyramids What do they show?

2. Population Pyramid • Shows age structure • Shows sex structure Of a place

4. What type of growth does this show? • Slow • Rapid • Moderate • Shrinking

5. Rapid • Triangular shaped

6. Rapid • Triangular shaped • Wide base

7. Rapid • Triangular shaped • Wide base Example: • Laos • Angola • LDCs

8. Rapid • Triangular shaped • Wide base Example: • Laos • Angola What do these places have in common? • LDC/Developing Nations (3rd world)

9. What type of growth does this show? • Slow • Rapid • Moderate • Shrinking

10. Moderate • Extended triangle • Base isn’t as wide

11. Moderate • Extended triangle • Base isn’t as wide Example: • Mexico • Brazil

12. Moderate • Extended triangle • Base isn’t as wide Example: • Mexico • Brazil What do these places have in common • More developed than LDCs, not as developed as others Mexico City Sao Paulo, Brazil

13. What type of growth does this show? • Slow • Rapid • Moderate • Shrinking

14. Slow • Column shaped • Population is neither increasing or decreasing Example: • United States

15. Slow • Column shaped • Population is neither increasing or decreasing Example: • United States What is the U.S. considered economically? • MDC

16. What type of growth does this show? • Slow • Rapid • Moderate • Shrinking

17. Shrinking • Top is wider than the base

18. Shrinking • Top is wider than the base • Population is aging • People having less kids

19. Shrinking • Top is wider than the base • Population is aging • People having less kids Example: • Italy • Latvia

20. Shrinking • Top is wider than the base • Population is aging • People having less kids Example: • Italy • Latvia What do these countries have in common? • Europe • MDC

21. More advanced

22. What can you tell by this place based on the population pyramid? • College town • External War • Internal War, famine, epidemic • Retirement community • Immigrant workers

23. College town • What populations are highest? • Because college students are usually between the ages of 17-23

24. What can you tell by this place based on the population pyramid? • College town • External War • Internal War, famine, epidemic • Retirement community • Immigrant workers Soviet Union, 1989

25. Internal War, famine, epidemic • Affects both men and women Soviet Union, 1989

26. What can you tell by this place based on the population pyramid? • College town • External War • Internal War, famine, epidemic • Retirement community • Immigrant workers

27. Retirement community • Lots of old people • Very few young people

28. What can you tell by this place based on the population pyramid? • College town • External War • Internal War, famine, epidemic • Retirement community • Immigrant workers

29. Immigrant workers • Most immigrant workers are men • What type of work? • Construction • What type of immigrant work do females do? • House work

30. What can you tell by this place based on the population pyramid? • College town • External War • Internal War, famine, epidemic • Retirement community • Immigrant workers

31. External War • Less men than women • Men usually fight in wars

32. Age-Dependency Ratio

33. Age-Dependency Ratio • Working population must support the non-working population. • What ages are considered non-working? • 0-14, 65 & up

34. Age-Dependency Ratio Formula

35. Age-Dependency Ratio Formula • The answer tells us how many dependents there are per 100 people working • For example:

36. Age-Dependency Ratio FormulaExample: Mali - Africa • Population <15: 48 • Population 65+: 3 • Population 15-64: 49 • 48 + 3 = 51 • 51/49 = 1.04 • 1.04 x 100 = 104 • This means that for every 100 people that work, they have to support 104 people. • That’s bad!!!

37. Disadvantages • Wide base means there are a lot of kids • Young kids can’t support themselves • Large burden on society, especially their mothers • Have to support large families rather than working • LDC

38. Age-Dependency Ratio FormulaExample: Germany - Europe • Population <15: 14 • Population 65+: 20 • Population 15-64: 66 • 14 + 20 = 34 • 34/66 = 5.15 • 5.15 x 100 = 51.5 • This means that for every 100 people that work, they have to support 52 people. • That’s better, but look how many older people there are than younger people.

39. Disadvantages • What are the two largest percentages of age ranges? • What problem do you think Germany will have in 15 -20 years? • People will start to retire, working population will have a hard time supporting them.

40. Disadvantages • How can Germany support these people even though they aren’t having many children? • Immigration!

41. The Demographic Transition Model

42. The Demographic Transition Model

43. The Demographic Transition Model

44. Stage 1 – Low Growth • CBR and CDR are high • What does this mean for population growth? • Low

45. Stage 1 - Low Growth • Why are the birth rates and death rates so high?

46. Sweden’s DTM

47. CDR - Poor Medicine/Doctors • Before modern medicine • Did not sanitize • Did not know about germs • No antibiotics Dr. Nick

48. CDR - Infant Mortality • Poor medicine/doctors • People had to have more kids because chances were that at least ½ would die

49. CBR - Infant Mortality • Most people lived on farms • Needed kids to work on the farm • People had to have more kids because chances were that at least ½ would die

50. Stage 2 – High Growth • Birth Rate still high • Death rate falling • What dos this mean for population growth? • Rising