SME
Human Geography · Problem type
Dependency ratio from age groups
Use this for “A country has 2.4 million people under 15, 6 million aged 15–64 and 1.2 million aged 65 and over. What is its dependency ratio?”
Diagram
Youth
ratio
=
100
×
2,400,000
6,000,000
=
40;
old-age
ratio
=
100
×
1,200,000
6,000,000
=
20.
Dependency ratio = 40 + 20 = 60 dependents per 100 people of working age.
The five-year bars are shaped expansive and add up to each group’s total; the shape inside a group is drawn, not data.
This is an example. Type your own values to start a new problem.
DR
=
+
P₁₅₋₆₄
×
100
YDR
Youth dependency ratio
calculated
ODR
Old-age dependency ratio
calculated
Formulas
YDR = 100 × P₀₋₁₄ ÷ P₁₅₋₆₄
40
=
100
×
2,400,000
6,000,000
ODR = 100 × P₆₅₊ ÷ P₁₅₋₆₄
20
=
100
×
1,200,000
6,000,000
DR
=
100
×
P₀₋₁₄ + P₆₅₊
P₁₅
₋₆₄
60
=
100
×
2,400,000 + 1,200,000
6,000,000
Assumptions
•
Dependents are under 15 or 65 and over; ages 15 to 64 are the working ages, whether or not people work.
•
Each ratio is dependents per 100 people of working age, so countries of different sizes compare.
•
The ratio counts heads, not earnings; the bars inside each age group are drawn to a typical shape.
Step-by-step
WE KNOW
P₀₋₁₄ = 2,400,000, P₁₅₋₆₄ = 6,000,000, P₆₅₊ = 1,200,000
FIND
youth dependency ratio (YDR), old-age dependency ratio (ODR), total dependency ratio (DR)
Step 1 · Find youth dependency ratio (YDR)
Use YDR = 100 × P₀₋₁₄ ÷ P₁₅₋₆₄
Children under 15 for every 100 people aged 15 to 64.
YDR
=
100
×
2,400,000
6,000,000
YDR
=
240,000,000
6,000,000
YDR = 40
Step 2 · Find old-age dependency ratio (ODR)
Use ODR = 100 × P₆₅₊ ÷ P₁₅₋₆₄
People 65 and over for every 100 people aged 15 to 64.
ODR
=
100
×
1,200,000
6,000,000
ODR
=
120,000,000
6,000,000
ODR = 20
Step 3 · Find total dependency ratio (DR)
Use DR = 100 × (P₀₋₁₄ + P₆₅₊) ÷ P₁₅₋₆₄
All dependents, young and old, per 100 people of working age.
DR
=
100
×
2,400,000 + 1,200,000
6,000,000
DR
=
100
×
3,600,000
6,000,000
DR
=
360,000,000
6,000,000
DR = 60
Check
Put the numbers back in. Both sides should match.
40
=
100
×
2,400,000
6,000,000
✓
20
=
100
×
1,200,000
6,000,000
✓
60
=
100
×
2,400,000 + 1,200,000
6,000,000
✓
Topic check
See what you know: 5 questions on this topic
New questions each time. Pass to mark it complete.
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