Help pls
According to global data from 2018, Niger had a natural rate of increase equaling 3.8% and Bulgaria equaled −2.8%. What process was used to calculate this statistic?

A) Averaging the fertility rate for the past 100 years
B) Multiplying the crude birth rate by 10
C) Subtracting the crude death rate from the crude birth rate
D) Dividing the crude birth rate by the sex ratio
E) Adding the death rate to the fertility rate and dividing by two