Birth rate
As of 2017, Niger has the highest birth rate in the world with 49.443 per thousand people. 
Japan has one of the lowest birth rates in the world with 8 per thousand people.
While in Japan there are 126 million people and in Niger 21 million, both countries had around 1 million babies born in 2016.
List of countries by infant and under-five mortality rates
The infant mortality rate is the number of deaths of infants under one year old per 1,000 live births. This rate is often used as an indicator of the level of health in a country. The infant mortality rate of the world is 49.4 according to the United Nations and 34.1 according to the "CIA World Factbook".