Growth like that described above is called exponential growth. In exponential growth, the population increases by a constant multiplier (r) at each time step. You can see that the population grows slowly at first and then at a rapidly accelerating rate.

Exponential growth results from G = r * N, when r is a constant.

For those of you familiar with calculus,
the integrated form of G = rN (dN/dT = rN) is Nt = N_{o}^{rt}, where
r = the exponent.

Human growth has not been not exactly exponential,
because our r has not been constant. In fact, our growth has actually
been *faster than exponential*, because r has generally increased
over the course of human history.

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