This is the most common, the most easily computed and the most easily understood measure of fertility. The crude birth rate is the ratio of the total registered live births in some specified year in a particular area to the total mid-year population of that area multiplied by 1,000. It is computed in the following manner:
The crude birth rate of 17.56 indicates that in the sample area of Calcutta city, there had been 17.56 births per 1,000 populations during 1967-68.
The crude birth rate is an important measure of fertility, for it directly points to the contribution of fertility to the growth rate of the population.
The computation of the crude birth rate is easy and quick, for it requires the minimum of data. It indicates the level of the fertility of a society. But, as its name suggests, the crude birth rate is only a crude measure of fertility and suffers from several weaknesses, which are similar to those of the crude death rate.
Several refinements in his measure have been introduced to ensure that fertility is measured in a more sensitive manner.