The formula for exponential population growth is:

Exponential growth form can be represented mathematically by the following exponential equation: $\frac{d N}{d t}=(\mathrm{B}-\mathrm{D}) \times \mathrm{N} \mathrm{B}=$ Birth rate, $\mathrm{D}=$ Death rate Let $(B-D)=r$ or intrinsic rate of growth. Then, $=r \times n$ where $d$ is the rate of change, $\mathrm{N}=$ number of existing individuals. $t=$ time and $r=$ intrinsic rate of natural increase represents the rate of change in population size.