It's because they want people to mentally subtract "military-age males" from the figures.

"Children, defined as people under 18"

People under 18 whom it defines as children

Aside from including your 'meme phrase', I don't see the difference

Oh, didn't know about the meme, thanks

No? Like fucking take the effort to verify you’re claims my dude

https://www.un.org/en/global-issues/youth

“There is no universally agreed international definition of the youth age group. For statistical purposes, however, the United Nations—without prejudice to any other definitions made by Member States—defines ‘youth’ as those persons between the ages of 15 and 24 years. This definition, which arose in the context of preparations for the International Youth Year (1985) (see A/36/215), was endorsed by the General Assembly in its resolution 36/28 of 1981. All UN statistics on youth are based on this definition, as is reflected in the annual yearbooks of statistics published by the UN system on demography, education, employment and health.”

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