The population growth rate is a metric of how quickly a population increases in size. it is dependent upon the population's death and birth rates human population growth rates fluctuate over time. for example, after the industrial revolution in the 18th century in europe and north america, the human population growth rate soared because better health care and nutrition led to lower mortality rates. in the past few decades, human population growth has significantly decreased in some areas of the world. despite a trend of lower birth rates in many regions during the past century, the global human population, which scientists estimated to be 7.5 billion in 2017, is increasing at a growth rate of just over 1%. the projected global human population in if earth's population continues to grow at the current rate of 1.13%, what the year 2100? 25 billion 11 billion more than 30 billion 8-9 billion