Final answer:
The net reproductive rate (NRR) is calculated using the formula NRR = ∑ (lx * mx) for each age class. After calculation, the NRR for the given life table is found to be 2.53, indicating that the population is growing as this value is greater than 1.
Step-by-step explanation:
The net reproductive rate (NRR) is the average number of offspring that would be born to a female if she passed through her lifetime conforming to the age-specific fertility and mortality rates of a given year. To calculate NRR for this life table, you must use the formula NRR = ∑ (lx * mx), where lx is the survivorship rate (the proportion of individuals surviving to age x), and mx is the fecundity rate (the average number of offspring produced by a female at age x).
Let's calculate the NRR step by step:
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- Age 0: lx = 1.000, mx = 0.00 ==> NRR contribution = 1.000 * 0 = 0
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- Age 1: lx = 0.950, mx = 1.20 ==> NRR contribution = 0.950 * 1.20 = 1.14
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- Age 2: lx = 0.875, mx = 1.42 ==> NRR contribution = 0.875 * 1.42 = 1.2425
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- Age 3: lx = 0.188, mx = 0.75 ==> NRR contribution = 0.188 * 0.75 = 0.141
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- Age 4+: lx = 0.075, mx = 0.10 ==> NRR contribution = 0.075 * 0.10 = 0.0075
Add up these NRR contributions: 0 + 1.14 + 1.2425 + 0.141 + 0.0075 = 2.5305, which we can round to 2.53.
The net reproductive rate of 2.53 means that, on average, each individual in the population will contribute to just over two individuals for the next generation, assuming that current age-specific fertility and mortality rates remain constant. Since this number is greater than 1, the population is indeed growing.