poverty line 貧困ライン

poverty line （貧困ライン）とは貧困限界線。tree line(森林限界線）のように考えるといい。live below/under the poverty line のように使われます。2:07 she and her two children live far below the poverty line.

Suburb in Wealthy Illinois County Sees Unexpected Rise in Poverty
https://www.youtube.com/watch?v=FmyXzzSXwdc  2:56 many of those going hungry are kids. one in three children in Chicago are said to live below the poverty line.
Chicago crumbling in poverty
https://www.youtube.com/watch?v=TPLpbHZicko  0:53 (between) 15% and 22% of all children now live under the poverty line.　
A record number of poor Americans, in the shadow of US vote
https://www.youtube.com/watch?v=wle1j6tIE9g  1:53 up to a quarter of the population thought to be approaching the poverty line. ギリシャでは人口の1/4が貧困ラインに近づいている。
Retired Greeks pushed to breadline by crisis

参考リンク
http://bridge-english.blogspot.jp/2015/12/hand-to-mouth-existence.html  hand-to-mouth existence