>>Is 60% annual growth exponential?
>>I guess it is if the exponent is less than one.
>>If that's the case, isn't all growth exponential?
>
>"Exponential growth" is often used as "very fast", but technically, it refers to any curve that can be fit to a function of the type A * exp(Bt) for constants A and B, or equivalently, A * C^t for constants A and C. In less technical terms, if the ratio between two consecutive time periods is always the same (or at least similar). 60% growth means a increase by a factor 1.6. If that continues every year for several years, you do indeed get an impressive size (after a few years of course). An "exponential curve" can also go down, if the base ("C" in the second model equation above) is less than one. For example, the amount of material left in a radioactive decay.

And 0.1% annual growth is still exponential... if you multiply something by 1.001 many times over, it will grow. The press won't be impressed, though.