There are no countries currently in stage 1 of the population pyramids.
There are five stages of population pyramids.
Stage five countries the birth rates remain low, and the death rates go up. Because of this, countries have a negative NIR, which leads to the population decreasing. These countries have graying populations, with less men and women in their childbearing years.
A number of these governments promote pro-natalist policies to try and stunt the population decrease.
The population pyramids in these countries are wider at the top and start to look like an upside down pyramid.
Stage two has a high birth rate, but the death rate drops. Because of this the natural increase rate goes way up!
The population of these countries is rising and their doubling time is short. However, the population will not continue to go up at the same rate.
The population pyramids of these countries have a very wide base that gets thinner and thinner the higher you go
Population
Pyramids
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Diya Brijesh
Stage three the birth rate goes down, while the death rate remains low. The population continues to rise, but not nearly as much as stage two. The natural increase rate is still positive, but not as high as in stage two.
Stage three countries start to become more industrialized, which means they are more urbanized and the total fertility rate goes down.
The population pyramids of these countries are wider in the middle ages and have more of a pear shape.
Stage four countries the birth rates get lower, while death rates start to rise as people are getting older. The natural increase rates (NIR) in these countries is close to zero.
For example, in the United States the NIR would be zero if you took away the net-in migration that it has every year.
The population pyramids of these countries are even throughout the age groups and somewhat resembles a skyscraper.
