PAPP101 - S08: Life Tables (II)

The expectation of life (cont.)

The stationary population

Before we leave this session we must mention a demographic concept known as the stationary population. This is an important concept that will be picked up later in the Population Dynamics session.

The stationary population is the _nL_x column but viewed in a different way. At present we view the _nL_x column as a number of person-years. Diagrammatically it could be considered as below.

Click on the arrows beneath Figure 1 for more information.

Figure 1. The l_x column plotted with an associated L_x measure for a specific age group shown as the area under the curve.

That is, that the person years between specified ages could be seen as the area under the l_x curve.