Demography is the science of human population. It studied everything about people such as your interests, occupation, gender, age, etc. Researchers typically focus on the force because of their customers is that people should have to learn to be able to grow well. And the change in the number or the tendency of a small part of this force can also cause many large fluctuations, it brings both benefits and harm. Thanks to the fluctuations created opportunities for business development companies.
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