The demographic transition is the measurements created from the gradual shift in birth and death rates from the primitive to the modern condition in the industrialized societies (Wright, et al, 2011). Our understanding of the demographic transition includes the crude birthrate (CBR) and the crude death rate (CDR). The CBR and CDR are the number of births and deaths, respectively per thousand of the population per year. With data given per thousand of the population, the populations of different countries can be compared regardless of their total size. In using the term “crude” we are implicating that no consideration is given to what proportion of the population is old or young, male or female. CDR is subtracted from CBR which gives the increase or decrease per thousand per year and dividing this result by ten yields the percent increase or decrease of the population (Wright, et al, 2011).
The four phases of the demographic transition are such as phase one in which there is the primitive stability resulting from a high CBR with an offset from an equally high CDR. In phase two is a declining CDR resulting from the epidemiologic transition. Fertility and the CBR remain high which activates population growth in this phase II. Phase III has a declining fertility rate however the population growth is still significant. Phase IV is reached when modern stability is achieved by a continuation of a low CDR and CBR.
In the epidemiologic transition there has been a high crude death rate. This would include forty or more per thousand for most societies. Getting to the middle of the nineteenth century the epidemics and other social conditions that were responsible for death rates began to recede with death rates in Europe and North America declining. The decline was gradual in now-developed countries and finally stabilized at a CDR of about ten per thousand. In the present