Some defenitions

LIfe expectancy- a average life in the country
Birth Rate- how many births per 1000
Death rate- number of deaths per 1000
RNI ( rate of natural increase) - birth rate minus death rate
TFR ( total fertility rate)- average number of children born to a women to a given population.
I the TFR to stay average is 2.1
net migration rate- number of people immigrants/emigrants going in and out of a country.

• United stats is 4.32 positive
• Push and pull factors make people leave because of bad health or want a cheaper way of life

Population pyramid- Shows ages of men and women in the given population of a country.