Description:
About the population pyramid and data
Population pyramids are commonly used by demographers to illustrate age and sex structure of a country's population. Countries that are expected to grow rapidly typically have a large number of individuals in their reproductive years and the population pyramid is wider or"heavier" at the bottom. In contrast, populations that are expected to have slow, zero, or negative growth typically have more individuals beyond reproductive age, and their pyramids tend to be "top heavy".
The population distribution of Mexico is quite different from that of the US and Germany in that over 50% are under age 25. Even more significant is the fact that 33% of the current population of women are of pre-reproductive age (0-14 years) and 49% of reproductive age (15-44). With a such large proportion of young females, Mexico's population is expected to rapidly increase in the near future. Some demographers classify Mexico as a transitional country, moving from a farm based to an industrial based economy. In more industrialized economies, birth rates drop (for reasons including better access to family planning and increased job opportunities for women) and eventually approach death rates. As these rates converge, overall population growth decreases. As Mexico becomes more industrialized will its population growth approach zero? Will the total population eventually level off?
Making predictions about a country's future population is aided by studying age cohorts (groups) such as those defined in the accompanying data set. Instead of considering a single growth or birth rate for the entire population, demographers estimate each cohort's birth and death rate, so as to increase the predictive power of their models. Also taken into consideration are immigration and emigration from each cohort to other countries. (For Mexico, emigration is significant among males of working ages as many relocate to the United States to work.) Using dynamic cohort models, population pyramids can be computed predicting population structural changes over time. For an example of these pyramids visit the extraordinary website http://www.census.gov/ipc/www/idbpyr.html. This site is part of the much larger US Census International Data Base (IDB) website where additional country by country demographics can be found.
