人们是什么时候意识到人口增长问题的?（最好用英语回答）急!

When too many people were laid-off and too many gradulaters couldn't find their jobs.
As far as I am concerned,no country can afford everyone except in Communism,but now we are in the primary process of socialism.
By the way the question asked when did.

When they found their productions can't afford everyone in their country.