The total fertility rate in an economy is defined as

Explanation

The total fertility rate (TFR) of a population is the average number of children that are born to a woman over her lifetime if they were to experience the exact current age-specific fertility rates (ASFRs) through their lifetime and they were to live from birth until the end of their reproductive life. This means by the end of their child bearing age. https://www.civilsdaily.com/news/fertility-levels-drop-below-one-in-many-asian-nations/