Tempo-adjusted total fertility rate

Definition

The term adjusted total fertility rate or tempo-adjusted total fertility rate refers to a modified form of the total fertility rate that accounts for the tempo effect in a manner that provides (arguably) a better estimate of the completed fertility rate in the long term.

The standard definition of total fertility rate is that it is the sum of the age-specific fertility rates for all ages. Alternatively, it is the number of live births a hypothetical woman would have if she passed through her childbearing years conforming to the age-specific fertility rate of this particular year. If age-specific fertility rates hold constant over time, i.e., in the absence of tempo effects, the total fertility rate would equal the completed fertility rate for a birth cohort of females who have completed their childbearing years.

In the presence of tempo effects, we expect that age-specific fertility rates will change over time. The tempo-adjusted total fertility rate attempts to use data measuring the number, nature, and temporal distribution of live births in the current year only to estimate how these changes will unfold.