Description

Given the observed populations in two known years, determines the geometric growth rate observed in the period and predicts the future population through this rate.

Calculation Methods

Geometric method

This method uses the data from two known years to determine the population growth rate and predict future population. The formula used is:

$$P_y = P_1 \times \left( \frac{P_2}{P_1} \right)^{\frac{t_y - t_1}{t_2 - t_1}}$$

Input and Output Parameters

Parameter	Default Units	Description
Year 1	-	First year of observation
Year 2	-	Second year of observation
Year of interest	-	Year for which the prediction is made
Population 1	-	Population observed in Year 1
Population 2	-	Population observed in Year 2
Predicted population's size	-	Estimated population for the year of interest