Understanding Population Growth and Migration: A Case Study

Understanding the dynamics of population growth and migration is crucial for communities and governmental planning. This article delves into a specific scenario where a town's population undergoes both natural growth and a decrease due to emigration. By breaking down the process annually, we can calculate the overall growth percentage over a span of three years.

Initial Assumptions and Calculation Method

Let's assume the initial population of a town is 100. The town experiences a natural population increase of 5 people per year but also loses 1 person due to migration each year. This scenario provides an opportunity to calculate the effective population increase over time.

Calculation of Population Growth Over Three Years

First Year:

Initial population: 100 Increase due to natural growth: 5 Total population after growth: 105 Decrease due to migration: 1 Population after decrease: 105 - 1 104

Second Year:

Initial population: 104 Increase due to natural growth: 5 Total population after growth: 104 5 109 Decrease due to migration: 1 Population after decrease: 109 - 1 108

Third Year:

Initial population: 108 Increase due to natural growth: 5 Total population after growth: 108 5 113 Decrease due to migration: 1 Population after decrease: 113 - 1 112

Now, let's calculate the population increase percentage over the three years:

Population increase percentage over three years

(112 - 100) / 100 times; 100 12%

Effective Annual Rate of Increase

The effective annual rate of increase can be calculated using the compounded growth formula:

(105 / 100) times; (105 / 100) times; (105 / 100) 1.124864

This results in an overall increase of 12.4864% over three years.

Calculation Summary

1. Initial population: 100

2. Natural increase in first year: 5 times; 1 5

3. Net increase in first year: 5 - 1 4

4. Population at the end of first year: 100 4 104

5. Natural increase in second year: 5 times; 1.04 5.2

6. Population at the end of second year: 104 5.2 - 1 108.2

7. Natural increase in third year: 5 times; 1.0416 5.208

8. Population at the end of third year: 108.2 5.208 - 1 112.408

9. Increase percentage over three years: (112.408 - 100) / 100 times; 100 12.408%

Conclusion

Through the analysis, we can see how the balance of natural population growth and emigration affects the overall population over time. This method of calculation is useful for communities and policymakers to better understand and plan for future growth or decline. By adjusting the rates of growth and migration, one can predict future population trends and make informed decisions.