Exponential is a per capita rate.
You need to set the initial size of the population the constant in which the population grows, and make sure to make the flow be a bi-flow in order to have a population decrease. Phase Diagram - use the phase diagram to find the equilibrium points and to decide whether they are stable or unstable. This Phase Diagram show that the only equilibrium is at zero because this is the only x-intercept. It is an unstable equilbrium with exponential growth the population will just continue to grow. Solution Curves - use the solution curves to see the general behaviors of the model.