Population Growth Calculator
This population growth calculator estimates how a population changes over time based on various factors such as birth rates, death rates, and migration.
Suppose a city has an initial population of 100,000 and experiences a 2% annual growth rate. Using the population growth calculator, you can determine that after 10 years, the population would grow to approximately 121,899 people, assuming consistent growth.
Population Growth Calculation Chart
Year | Initial Population | Growth Rate | Population Increase | Final Population |
---|---|---|---|---|
1 | 100,000 | 2% | 2,000 | 102,000 |
2 | 102,000 | 2% | 2,040 | 104,040 |
3 | 104,040 | 2% | 2,081 | 106,121 |
4 | 106,121 | 2% | 2,122 | 108,243 |
5 | 108,243 | 2% | 2,165 | 110,408 |
Population Growth Formula
The basic formula for population growth is:
P(t) = P₀ × (1 + r)ᵗ
Where:
- P(t) is the population after time t
- P₀ is the initial population
- r is the growth rate (as a decimal)
- t is the time period
Using our previous example:
- P₀ = 100,000
- r = 0.02 (2% expressed as a decimal)
- t = 10 years
P(10) = 100,000 × (1 + 0.02)¹⁰ = 121,899
How do you calculate population growth rate?
To calculate the population growth rate the formula is:
r = (P(t) / P₀)^(1/t) - 1
For example, if a town’s population increased from 50,000 to 65,000 over 5 years:
- P₀ = 50,000
- P(t) = 65,000
- t = 5 years
r = (65,000 / 50,000)^(1/5) - 1
r ≈ 0.0539 or 5.39% per year
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