Ages at death in UK Life Tables

What do ‘numbers dying between exact ages’ mean in life tables?

Life tables are an important demographic tool. These tables help actuaries and others analyse death rates and life expectancy.

How do analysts calculate national life tables?

Step 1: The analyst starts with 100,000 simultaneous births in one country, and of one sex. (This is often denoted l₀.)

Step 2: They multiply that population of 100,000 by the mortality rate between age 0 and 1 (denoted q₀). That gives the number of deaths at age 0 (d₀).

Step 3: They then subtract that number of deaths (d₀) from the living population (l₀). That gives the number surviving to age 1 (l₁).

Step 4: Analysts then apply this iterative process to age 110.

Wrangling the data

One measure of interest is the numbers of deaths by age in the synthetic cohort. Suppose there were 100,000 births, experiencing the period mortality rates at each age. From this calculation, there would be an expected number dying at each age.

The measure (dₓ) is also called the ‘numbers dying between exact ages x and (x+1)’. How does this measure differ between sexes and between nations?