The Total Fertility Rate (cont.)
Cohort fertility
Lexis diagram 2
This Lexis diagram depicts the cohort from the previous page. You can see that this approach has actually NOT captured a pure cohort and it is a strength of Lexis diagrams that they can reveal situations like this. Nevertheless we have to work with the data available to us and not get too worried about small concerns – demography is a pragmatic discipline. The cohort approach taken here has not been perfect but it is still a useful approach with a valid result.
