On the other hand, if a quantity is falling rapidly toward zero, without ever reaching zero, then we should probably choose the exponential decay model. In some applications, however, as we will see when we discuss the logistic equation, the logistic model sometimes fits the data better than the exponential model. Such phenomena as wildlife populations, financial investments, biological samples, and natural resources may exhibit growth based on a doubling time. We may use the exponential growth function in applications involving doubling time, the time it takes for a quantity to double.
Where A 0 A 0 is equal to the value at time zero, e e is Euler’s constant, and k k is a positive constant that determines the rate (percentage) of growth.
