How To Calculate Crude Birth Rate

Crude birth rate represents the childbirths per 1,000 people each year. This is a common measure of fertility for a given population. Statiticians use the crude birth rate in population geography and demography because it is a useful indicator in studies of population around the world. The crude birth rate could be of concern for particular countries who may be experiencing population decline or for national governments who are worried about population growth rates that are higher than their country can sustain.

1. Divide Midyear Population

The crude birth rate (CBR) is equal to the number of live births (​b​) in a year divided by the total midyear population (​p​), with the ratio multiplied by 1,000 to arrive at the number of births per 1,000 people.

2. Write Out the Formula

The formula for crude birth rate is:

\(\text{CBR} = \frac{b}{p} × 1,000\)

3. Sample Equation

For example, in 2007, there were 3,250 births in a city with population of 223,000. Therefore:

\(\text{CBR} = \frac{3,250}{223,000} × 1,000 = 14.57\)

So, there were 14.57 births for every 1,000 people in the city.