Question: what is the exponential growth and decay?
Answer: Exponential Decay: y = a(1 - r)x. Remember that the original exponential formula was y = abx. You will notice that in these new growth and decay functions, the b value (growth factor) has been replaced either by (1 + r) or by (1 - r). The growth "rate" (r) is determined as b = 1 + r.