Has a beginning, middle, end, and is irreversible.
Four stages. You cannot go back a stage.
Demographic Transition: Stage 1(low growth)
CBR's and CDR's varied, making growth virtually 0%. No more countries in this stage.
Demographic Transition: Stage 2(high growth)
CDR falls, and CBR stays the same. NIR is high so pop. grows quickly.
conjunction of major improvements in industrial tech. that transformed process of manufacturing goods and delivering them to market
Demographic Transition: Stage 3 (moderate growth)
When CBR drops sharply CDR keeps falling but at a slower rate than stage 2, so rate of NIR is more modest.
Demographic Transition stage 4 low growth
CBR declines so it equals CDR. NIR is 0.
Social customs play a part: AKA people don't want kids.
total fertility rate(TFR)
demographers define zero population growth as this. a TFR of 2.1 makes ZPG.
Population in a country is influenced by dem. trans. in two ways:
percent of population in each age group, and distribution of males and females
percent of total population in five year groups with youngest at base and oldest on top.
Males on left, females on right.
number of people too young or old to work, compared to number of people in productive years.