for rates
Higher child mortality causes higher fertility rates. Rapid population growth has been a temporary phenomenon in countries around the world. Rapid population growth starts when the health of the population improves and the mortality rate in a population decreases while the birth rate stays as high as before.
for population
Population growth is still fast: Every year 140 million are born and 58 million die – the difference is the number of people that we add to the world population in a year: 82 million. ... In red you see the annual population growth rate (that is, the percentage change in population per year) of the global population.
source - ourworldindata.org