[forapurpose]

Extreme poverty, in this case, is a measure developed by economists and not by politicians, and AFAIK the definition hasn't changed significantly in many years.

As the parent says, not being in 'extreme poverty' doesn't tell us much about one individual. They could have $2.50 per day; they could be Bill Gates (of course, it tells us a lot if someone is living on less than $1.90/day; that's a much smaller range). But the aggregate measure is meaningful: The number is decreasing and has been for decades - a miracle relative to world history - bringing hundreds of millions of people of out hopeless poverty; just look at India, China, and Latin America. Yes, some are still very poor, but we can use other measures to examine that such as median income (which also has changed dramatically).

Also, 'poverty' in wealthy countries and 'extreme poverty' used in this measure are entirely different things. If you're reading this, $1.90/day probably won't pay for your electricity or water usage for the day, much less food, shelter, health care, education, transportation, etc.