Per Capita — Definition, Formula & Examples
Per capita is a Latin phrase meaning 'per person' or 'for each person.' It describes a quantity divided equally among every individual in a group or population.
A per capita value is a rate obtained by dividing an aggregate quantity by the total number of individuals in the relevant population, yielding an average amount per person.
Key Formula
Where:
- = The aggregate amount being measured (e.g., income, water usage, emissions)
- = The total number of people in the group
How It Works
To find a per capita value, divide the total amount by the number of people. For example, if a city produces 900,000 tons of waste and has 300,000 residents, the waste per capita is 3 tons per person. Per capita figures let you compare groups of very different sizes on equal footing — a small town versus an entire country, for instance.
Worked Example
Problem: A country has a total income of $8,000,000,000 and a population of 2,000,000 people. What is the per capita income?
Set up the division: Divide total income by the population.
Calculate: Simplify the fraction.
Answer: The per capita income is $4,000 per person.
Why It Matters
Per capita values appear constantly in social studies, geography, and science when comparing countries or cities. Economists use GDP per capita to measure standard of living, and environmental scientists use emissions per capita to assess each nation's impact on climate change.
Common Mistakes
Mistake: Comparing raw totals instead of per capita values when populations differ greatly.
Correction: A country with 1 billion people will almost always have a larger total than one with 5 million. Divide by population first so the comparison is fair.