Biology & Life Sciences
Intermediate

Population Doubling Time

Time for a population to double.

Formula

td=ln⁡2rt_d = \frac{\ln 2}{r}

Variables

rGrowth rate

Example

r=0.02 ⇒ 34.7 yr

Did You Know?

The rule of 70 estimates doubling time, so a 2% growth rate doubles a population in about 35 years.

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