Demographic Transition Overview

Definition: Process describing how crude birth rates, crude death rates, and population growth rates ( $r$ ) change as countries become more industrialized.
Key Variables:
- Crude Birth Rate
- Crude Death Rate
- Population Growth Rate ( $r$ )

Stage 1: Pre-industrial Stage
- High birth rates and high death rates due to harsh living conditions and high infant mortality.
- Population growth is very small or close to zero.
Stage 2: Transitional Stage
- Industrialization begins, bringing improved healthcare, increased food production, better nutrition, and wealth.
- Death rates drop while birth rates remain high due to a lag in education.
- Population grows very rapidly.
Stage 3: Industrial Stage
- Widespread industrialization with higher high school and college education rates, increased job opportunities for women, and higher costs of raising children.
- Improved access to birth control and reduced infant mortality.
- Birth rates drop toward death rates, resulting in a much slower population growth rate.
Stage 4: Post-industrial Stage
- Birth rates continue to decline, equaling or falling below death rates.
- Results in zero population growth or negative population growth (declining population).

Developing Countries: Located in earlier stages with rapidly exploding populations, creating challenges such as famine, hunger, disease spread, and political problems (e.g., Somalia).
Developed Countries: Positioned in industrial or post-industrial stages (e.g., Italy).
Global Trend: World population growth rate has been reducing over past decades down to $1.13$ and dropping toward zero population growth.