A population pyramid shows the population of a certain age group. It splits the population of male and female. These are helpful for analysis.$^0$
When the population pyramids have a wider base, they are most likely a developing country as their birth rate is high. When the pyramid looks inverted, it is most likely a developed country as both death and birth rates have fallen. This country could also later experience a population crisis.$^0$
There are three general components of the DTM. Crude birth rate(CBR), crude death rate(CDR), total population growth(TPG). These three components come together to represent the total economic progression of a country.$^1$
The CBR and CDR are high, and as a result the TPG is low. However, the CDR is slightly lower than the CBR. This results in the TPG increasing.$^1$
The CBR stays constant in this stage. However the CDR declines. This results in the rapid increase of the TPG.
In this stage CDR is constant. The CBR declines. This results in a decrease in the speed of the growth of the TPG.
Both the CDR and the CBR are low.
The CDR increases and the CBR decreases. This results in the TPG decreases. This is caused by the older population from stage 2 dying off.