geography 2.3'2.5

unit 2 (2.3-2.5)

crude birth rate

CBR

TFR

Total Fertility Rate

Immigration

in

emigration

out

Dependency ratio

14 years and under plus elderly

How do geographers calculate population growth and decline

RNI=CBR-CDR

CDR

crude death rate

numer of deaths in 1 year per 1000 people

IMR

Infant mortality rate

NIR and RNI

Natrusl increase rate or rate of natrual increase

baby boom

ecenomic prosperity world war

DTM

Demographic Transition Model

DTM stage 1

(High Fluctuating) features high birth and death rates, leading to slow population growth.

Stage 2

(Early Expanding), death rates fall while birth rates remain high, resulting in a population "explosion".

stage 3

(Late Expanding) sees birth rates fall, slowing population growth. 

stage 4

(Low Fluctuating), both birth and death rates are low, leading to a stable or stationary population

stage 5 

birth rates fall below death rates, causing population decline.  

ETM stage 1 

pestilence and famine 

ETM stage 2

receeding pandemics

How do geographers calculate population doubling time

dividing 70 by the population's annual percentage growth rate

Rule of (70)

ETM stage 3

Degenerative and human made diseases

ETM

Delayed degenerative diseases

ETM stage 5

Reemergence of infectious diseases

ETM

Predictable stages in disease  and life expectancy that countries experience as they develop which corresponds with the stages of the DTM. 

Youth dependent age 

10-14 years

Triangle pyramid means what

wide base more growth and fast popuation growth

bishop hat pyramid

slower population growth -population starting to age

rectangle shape pyramid

zero population growth  stable population 

inverted triangle pyramid

base smaller than top , negative population growth, population decline

Population composition

age , structure, sex ratio, ethnic diversity

What is a cohort 

a group who share common characteristics or experiences within a period

Dependency Ratio formula

dividing the combined population of youth dependents (under 15) and elderly dependents (65 and over) by the working-age population (15-64) and then multiplying by 100 to express it as a ratio per 100 working-age people. 

dtm stage 1 name

high stationary

dtm stage 2 name

early expanding

dtm stage 3 name

late expanding

dtm stage 4 name

low stationary

dtm stage 5 name

declining 

formula for NIR ?

CBR minus CDR

divided by 10