Halloween Blog

Today was halloween and in class we learned about population pyramids. Population pyramids are used to analyze growth or decline of fertility, mortality, and migration in cities. Population pyramids have three basic shapes. One of the shapes is an xmas tree. They measure when growth rates are slow, high birth rate, and short life expectancy. Another shape is a box. The box is usually associated with developed nations and slow growth. They also measure low infant mortality, slow population growth, and long life expectancy. The last common shape is a cup. The cup measures low birth rate, shrinking population, and long life expectancy.