Explanation
* The number of children born per 1000 people in the population in a year. This describes the crude birth rate, not the total fertility rate.
* The number of children born to a couple in their lifetime in a given population. This is close but not quite accurate. The total fertility rate is calculated for women, not couples.
* The birth rate minus death rate. This defines the rate of natural increase, which indicates population growth, not fertility.
* The average number of live births a woman would have by the end of her child-bearing age. This is the correct definition of Total Fertility Rate (TFR). It's a hypothetical measure assuming a woman lives through her childbearing years and experiences the age-specific fertility rates of a given period.
* In simple terms, TFR tells us the average number of children a woman would have if current birth trends continued.