Simple mathematics. If there are more births than deaths, the population will increase. If the reverse is true, the population decreases.
the answer is by comparing birthrates and death rates
Population decreases
demographic transition
Birthrates , death rates, women and male intercourse
because birth rates and death rates relate to population. the birth rate shows how much a population is increasing, and death rates show how much a population is decreasing. when you average the two out, it will give you the population(:
For the past century the birthrates in human culture have far out numbered the death rates which is why our world population has been steadily growing. People are living longer than they did in our past.
The ice in the box
When death rates lowered but birthrates stayed high, the population skyrocketed.
If birth rates exceed death rates, the population increases proportionally. If death rates exceed birth rates, the population decreases.
Birthrates , death rates, women and male intercourse
Birthrates, Death Rates, and the age structure of a population help predict why some countries have high growth rates while other countries grow more slowly.
The population grows every year because of the birthrates are higher and older people living longer, so the death rates has dropped.