In population dynamics, which measure is used to describe the number of deaths per year?

• A. Death rate
• B. Birth rate
• C. Growth rate
• D. Age structure

Answer: (A)

Death rate describes how many individuals die in a population over a given time, typically expressed per year and often per 1,000 people (the crude death rate). It is the standard way to quantify mortality in population dynamics, isolating how lethal the population is during that period. This differs from the birth rate, which counts new individuals entering the population, and from the growth rate, which reflects net change in population size after accounting for births, deaths, and sometimes migration. Age structure describes how the population is distributed across age classes, not the number of deaths per year. For example, if a population of 1,000 people experiences 12 deaths in a year, the death rate is 12 deaths per 1,000 people per year. This is the clearest way to measure mortality pressure over time.