Vital Statistics: Measures of Fertility and Mortality

Exam-Oriented Notes for JKSSB & Statistics Exams 
Prepared by Home Academy

Vital Statistics is a branch of statistics that deals with the collection, analysis, and interpretation of data related to births, deaths, marriages, fertility, and population changes. These indicators help governments and planners understand population growth, health conditions, and demographic transitions.

For competitive exams such as JKSSB, SSC, UGC NET, and Statistics exams, the most important measures are fertility rates and mortality rates.

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1. Measures of Fertility

Fertility refers to the actual reproductive performance of a population, measured by the number of births.

Important Fertility Indicators

Measure	Definition	Purpose
Crude Birth Rate (CBR)	Number of live births per 1000 population in a year	General fertility measure
Crude Fertility Rate (CFR)	Births per 1000 women of reproductive age	More accurate fertility indicator
Age Specific Fertility Rate (ASFR)	Births per 1000 women in a specific age group	Measures fertility by age
Gross Reproduction Rate (GRR)	Average number of daughters born to a woman	Replacement analysis
Net Reproduction Rate (NRR)	Average daughters surviving to reproductive age	Population replacement indicator

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2. Crude Fertility Rate (CFR)

Definition

Crude Fertility Rate measures the number of live births per 1000 women of reproductive age (15–49 years) in a given year.

Formula

CFR = Number of Live Births in a Year / Number of Women aged 15–49 year times *1000

Example

If births in a year = 12,000
Women aged 15–49 = 80,000

CFR = (12000 / 80000) × 1000 = 150

Important Points for Exam

Focuses only on women capable of reproduction

More reliable than Crude Birth Rate
Used in population growth studies
Expressed per 1000 women

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3. Age Specific Fertility Rate (ASFR)

Definition

ASFR measures the fertility rate of women in a specific age group.

Formula

ASFR = Number of Live Births to Women in Age Group / Number of Women in that Age Group * times 1000

Example

Births to women aged 20–24 = 5000
Women aged 20–24 = 40,000

ASFR = (5000 / 40000) × 1000 = 125

Age Groups Commonly Used

Age Group	Fertility Level
15–19	Low
20–24	Highest fertility
25–29	High
30–34	Moderate
35–39	Declining
40–44	Very low
45–49	Negligible

Exam Points

Most births occur in 20–29 age group

Used to calculate Total Fertility Rate (TFR)

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4. Gross Reproduction Rate (GRR)

Definition

Gross Reproduction Rate is the average number of daughters that would be born to a woman during her reproductive life (15–49 years) assuming no mortality.

Formula

GRR = TFR x {Proportion of Female Births}

Usually:

Female births ≈ 0.488

Interpretation

GRR Value	Meaning
GRR = 1	Exact replacement
GRR > 1	Population increasing
GRR < 1	Population declining

Exam Points

Considers only female births

Ignores female mortality
Used for population replacement studies

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5. Net Reproduction Rate (NRR)

Definition

NRR measures the average number of daughters born to a woman who survive to reproductive age.

Formula

NRR = GRR x {Probability of Survival of Females}

Interpretation

NRR Value	Population Status
NRR = 1	Stable population
NRR > 1	Population growth
NRR < 1	Population decline

Exam Points

Considers female mortality

More accurate than GRR
Used in demographic transition analysis

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6. Measures of Mortality

Mortality refers to the frequency of deaths in a population.

Important Mortality Indicators

Measure	Definition
Crude Death Rate (CDR)	Deaths per 1000 population
Infant Mortality Rate (IMR)	Deaths under age 1
Maternal Mortality Ratio (MMR)	Deaths during pregnancy
Age Specific Death Rate (ASDR)	Death rate in specific age group

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7. Crude Death Rate (CDR)

Formula

[
CDR = \frac{\text{Total Deaths in a Year}}{\text{Mid-Year Population}} \times 1000
]

Example

Deaths = 5000
Population = 200,000

CDR = (5000 / 200000) × 1000 = 25

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8. Infant Mortality Rate (IMR)

Definition

Number of infant deaths (below 1 year) per 1000 live births.

Formula

[
IMR = \frac{\text{Infant Deaths}}{\text{Live Births}} \times 1000
]

Latest Important Data (India 2024–2025 Estimates)

Indicator	Value
Infant Mortality Rate	~27 per 1000 births
Maternal Mortality Ratio	~97 per 100,000 births
Total Fertility Rate	~2.0

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9. Age Specific Death Rate (ASDR)

Formula

ASDR = Deaths in Specific Age Group /Population in that Age Group *times 1000

Importance

• Used in life tables

• Helps measure health conditions

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Revision Table (Very Important for Exams)

Indicator	Formula	Base
CFR	Births / Women (15–49) × 1000	1000 women
ASFR	Births in age group / Women in age group × 1000	1000 women
GRR	TFR × proportion of female births	Female births
NRR	GRR × survival rate	Female births surviving
CDR	Deaths / Population × 1000	1000 population
IMR	Infant deaths / live births × 1000	1000 births

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Previous Year Questions (PYQ)

PYQ 1

Crude Fertility Rate is calculated using:

A. Total population
B. Women aged 15–49
C. Married women only
D. Male population

Answer: B

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PYQ 2

Which measure considers female mortality?

A. GRR
B. NRR
C. CBR
D. ASFR

Answer: B

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PYQ 3

Infant Mortality Rate measures:

A. Deaths under age 5
B. Deaths under age 1
C. Maternal deaths
D. Adult deaths

Answer: B

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Most Expected MCQs for JKSSB (2026)

1

The reproductive age group of women used in fertility studies is:

A. 10–40
B. 15–49
C. 18–45
D. 20–50

Answer: B

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2

Which fertility indicator measures only female births?

A. ASFR
B. GRR
C. CBR
D. CDR

Answer: B

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3

NRR equal to 1 indicates:

A. Population decline
B. Population replacement
C. Population explosion
D. Zero population

Answer: B

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4

Crude Death Rate is expressed per:

A. 100
B. 1000
C. 10,000
D. 1 lakh

Answer: B

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5

Which measure is most accurate for fertility comparison?

A. CBR
B. CFR
C. ASFR
D. IMR

Answer: C

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One-Line Revision Points for Exam

Reproductive age group of women = 15–49 years

GRR counts daughters only
NRR includes mortality
IMR measures deaths below 1 year
CDR uses mid-year population
ASFR is most precise fertility indicator