growth : progressive development — Webster
Growth refers to an increase in some quantity over time. The quantity can be:
Physical (e.g., growth in height, growth in an amount of money)
Abstract (e.g., a system becoming more complex, an organism becoming more mature).
It can also refer to the mode of growth, i.e. numeric models for describing how much a particular quantity grows over time. — Wikipedia
Exponential growth is exhibited when the rate of change—the change per instant or unit of time—of the value of a mathematical function is proportional to the function’s current value, resulting in its value at any time being an exponential function of time, i.e., a function in which the time value is the exponent. Exponential decay occurs in the same way when the growth rate is negative. In the case of a discrete domain of definition with equal intervals, it is also called geometric growth or geometric decay, the function values forming a geometric progression. In either exponential growth or exponential decay, the ratio of the rate of change of the quantity to its current size remains constant over time. — Wikipedia
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