Demographic Transition

Today we read an article about demographic transitions. A demographic transition is a process of change in a societies population from high crude birth and death rates and low rate of natural increase to a condition of low crude birth and death rates, low rate of natural increase, and higher total population. There are four to five total stages and there is country that is in every one. The first stage is low growth. The is a very high CBR, very high CDR, and a very low NIR. When food was easily available and obtained the population grew. When food, animals, and vegetation were not as easily accessible, the population declined. The second stage is high growth. Stage 2 has high CBR, rapidly declining CDR, and very high NIR. Developed regions entered this stage after the Industrial Revolution while developing nations entered this stage in the medical revolution. Stage 3 has moderate growth. There was rapidly declining CBR, moderately declining CDR, and moderate NIR. This is when people decided to have fewer children causing a drop in CBR.  Developed regions entered in the first half of the twentieth century. Developing regions entered in the second half of the twentieth century. The fourth stage has low growth. There is very low CBR, low or slightly increasing CDR, and zero or negative NIR. This stage is when the CBR declines to the point where it equals the CDR and the NIR is zero. This is zero population growth.