Stage 1 has a high CBR and CDR with no natural increase. Most people in this stage die from natural disease. Ex: bubonic plague, eating a wild berry, etc. This stage doesn't really exist now. This stage has a population pyramid with rapid growth.
Stage 4
Stage 2 has a rapidly declining CDR along with high birth rates. Most of the causes of death in this stage is from pandemics. Ex: Covid-19, HIV/AIDS, swine flu, etc. The DTM of this stage is also classified as rapid growth due to the high birth rates and low death rates.
Hypothetical Stage 5
Stage 3 has a moderately declining CDR with a rapidly declining CBR. Also, the natural increase begins to balance. This stage has more human created diseases, and more chronic problems. Ex: cancer or a heart attack. The stage of DTM is classified as slow growth.
Thank you!
In Stage 4 we are delaying things that could kill us with medicine. Ex: Chemotherapy and heart surgery (as shown above). This stage has low birth and death rates with no natural increase (USA). The classification of this DTM is slow growth.
This stage is hypothetical. But, infectious diseases return like HIV/AIDS, malaria (as shown above), polio, etc. CDR>CBR. And there is a negative NIR. The DTM of this stage is in negative grotwth.