Fertility Migration Rates
1. **Problem statement:** We are given population data by age category along with births, immigrants, emigrants, marriages, and deaths. We need to calculate various fertility, migration, and marriage rates.
2. **Given data:**
- Population 0-14: 100000
- Population 15-25: 98345
- Population 25-30: 96963
- Population 30-35: 94948
- Population 35-40: 92252
- Population 45-49: 87080
- Population 50-55: 54584
- Population 56-60: 41587
- Population 0-4: 11000
(i) **General Fertility Rate (GFR):**
GFR is the number of births per 1000 women of reproductive age (usually 15-49).
Sum births in reproductive ages (15-49):
$$1655 + 818 + 686 + 1254 + 2183 + 4702 = 11298$$
Sum female population 15-49:
$$98345 + 96963 + 94948 + 92252 + 87080 = 469588$$
Calculate GFR:
$$GFR = \frac{\text{Total births}}{\text{Female population 15-49}} \times 1000 = \frac{11298}{469588} \times 1000 \approx 24.06$$
(ii) **Age Specific Net Migration:**
Net migration = Immigrants - Emigrants for each age group.
Calculate for each age group:
- 0-14: $1650 - 1400 = 250$
- 15-25: $880 - 600 = 280$
- 25-30: $700 - 300 = 400$
- 30-35: $1300 - 1000 = 300$
- 35-40: $2200 - 1200 = 1000$
- 45-49: $4600 - 33000 = -28400$
- 50-55: $12800 - 0 = 12800$
- 56-60: $11000 - 8000 = 3000$
(iii) **Total Fertility Rate (TFR) for age categories 15-25, 35-40, 45-49:**
TFR is the sum of age-specific fertility rates multiplied by the width of age intervals (usually 5 years).
Age-specific fertility rate (ASFR) = births / female population in age group
Calculate ASFR:
- 15-25: $\frac{818}{98345} \approx 0.00832$
- 35-40: $\frac{2183}{92252} \approx 0.02366$
- 45-49: $\frac{4702}{87080} \approx 0.054}
TFR = $5 \times (0.00832 + 0.02366 + 0.054) = 5 \times 0.086 = 0.43$
(iv) **Age Standardized Fertility Rate (ASFRate) for 15-25, 35-40, 45-49:**
Use a standard population to weight the ASFRs. Assume standard population weights $w_i$ for these age groups (not given, so assume equal weights for simplicity: $w_i = \frac{1}{3}$).
Calculate:
$$ASFRate = \sum w_i \times ASFR_i = \frac{1}{3}(0.00832 + 0.02366 + 0.054) = 0.02866$$
(v) **Age Standardized Marriage Rate for 15-25, 35-40, 45-49:**
Marriage rate = marriages / population in age group
Calculate marriage rates:
- 15-25: $\frac{13000}{98345} \approx 0.1321$
- 35-40: $\frac{12000}{92252} \approx 0.1300$
- 45-49: $\frac{12500}{87080} \approx 0.1435$
Age standardized marriage rate (equal weights):
$$\frac{1}{3}(0.1321 + 0.1300 + 0.1435) = 0.1352$$
(vi) **Age Standardized Migration Rate for 15-25, 35-40, 45-49:**
Net migration rate = net migration / population
Calculate net migration:
- 15-25: $880 - 600 = 280$
- 35-40: $2200 - 1200 = 1000$
- 45-49: $4600 - 33000 = -28400$
Migration rates:
- 15-25: $\frac{280}{98345} \approx 0.00285$
- 35-40: $\frac{1000}{92252} \approx 0.01084$
- 45-49: $\frac{-28400}{87080} \approx -0.3261$
Age standardized migration rate:
$$\frac{1}{3}(0.00285 + 0.01084 - 0.3261) = -0.1048$$
(vii) **Sex/Age Standardized Marriage Rate:**
Data for sex-specific population or marriages is not provided, so cannot calculate precisely.
**Final answers:**
- (i) General Fertility Rate $\approx 24.06$ births per 1000 women
- (ii) Age Specific Net Migration: see values above
- (iii) Total Fertility Rate $\approx 0.43$
- (iv) Age Standardized Fertility Rate $\approx 0.0287$
- (v) Age Standardized Marriage Rate $\approx 0.1352$
- (vi) Age Standardized Migration Rate $\approx -0.1048$
- (vii) Sex/Age Standardized Marriage Rate: insufficient data