Final answer:
The fertility rate is defined as the number of live births per the number of women aged 15-44 years at the midpoint of the year, typically shown as births per 1,000 women.
Step-by-step explanation:
The number of live births within a year per the number of women aged 15-44 years during the midpoint of the year is known as the fertility rate. The fertility rate is typically expressed in births per 1,000 women aged 15-44 and is used by demographers to understand and measure the reproductive potential and performance of a population. This rate quantifies the number of live births a woman is expected to have over her lifetime and is influenced by various factors, including but not limited to societal norms, health services, and laws restricting the number of births. For example, in China, the fertility rate saw a significant decline after the introduction of a policy limiting women to having one child in 1979.