This happens when there are relatively few children (because of the fall in fertility), relatively few older people (because of higher mortality previously), and lots of economically active adults, including, often, many women, who enter the labour force in large numbers for the first time.

ECONOMIST: Demography

Governments will also decide how to stick to the task and timetable they set themselves to reach an effective, fair and ambitious universal climate agreement that is to be adopted in 2015 and to enter into force from 2020, and to raise the current inadequate global ambition to address climate change and its impacts before 2020.

UNESCO: Basic Sciences

It's estimated that 18 million new Chinese workers will enter the mainland work force annually, with no end in sight.

FORBES: A river runs deep