All vertebrates experience boom and bust, in demographic terms.

FORBES: PETA Has It All Wrong

He said there was a changing demographic in terms of an ageing population but there was also a shortage of beds at the hospital.

BBC: Ulster Hospital

They would place a limit on immigration from outside the European Union, a misguided idea that Mr Cameron has at least taken care to justify in terms of demographic change rather than race.

ECONOMIST: David Cameron

What would be nice to see is a breakdown not just of the age demographics on Facebook, but also how active each age demographic is on Facebook, in terms of number of posts per day or amount of time spend on the social network.

FORBES: Top Facebook Trends In 2010 Show That It's a Teen's Social Network

We have a whole chapter on strengthening the American labor force, because that's where we certainly talk about, certainly in terms of this recession, the degree to which different demographic groups -- young people, blacks and African Americans -- all that have seen higher unemployment rates relative to the average.

WHITEHOUSE: Press Briefing