The Total Fertility Rate (cont.)
Cohort Fertility (cont.)
Some pages back we saw a graph of the period TFR plotted over a long series for France. Here it is again:
Figure 6. France: Total period fertility rate by year
with Cohort TFR superimposed for appropriate period
If we added the Cohort Fertility Rate what would it look like? Press on the graphic to reveal.
Figure 6. France: Total period fertility rate by year
with Cohort TFR superimposed for appropriate period
You can see that the Cohort TFR – also known as the Completed Family Size – is a much smoother series that irons out a lot of the tempo effects of the period TFR. It also represents a truer version of the series as it shows the true final outcome of women from different birth cohorts. The downside is that we can only calculate it historically and we lack very recent estimates.