LONDON (Thomson Reuters Foundation) - Almost 90 percent of people incorrectly believe that extreme poverty has become worse or not changed in the past 25 years, said a study published on Thursday, voicing concerns that public pessimism threatens to stall efforts to end poverty.

In a survey of some 26,000 people across 24 countries, 87 percent of respondents said they believed extreme poverty had not improved over the past two decades - while only one percent knew poverty rates had halved.

Since 1990 more than one billion people have been taken out of extreme poverty - defined as living on a daily income of less than $1.25 - with the proportion living in poverty in developing regions falling to 14 percent in 2015 from almost half.

But with 800 million people still living in extreme poverty, the study by Dutch research firm Motivaction with charities Oxfam and Global Citizen said the public needed to be more engaged than ever or risk the achievements of recent decades.

“It’s only when people understand that the battle has been so successful in the last 20 years that they will be engaged and realise what they can do to help,” Oxfam spokesman Matt Grainger told the Thomson Reuters Foundation.

“It’s one of the biggest achievements in recent human history and it’s going virtually unrecognised ... (and this) really threatens to stall this successful story that we’ve seen so far.”

The study comes a year after world leaders agreed on an ambitious new set of global goals designed to improve lives in all countries by 2030.

The U.N.’s 17 Sustainable Development Goals (SDGs) with 169 targets are a roadmap to end poverty and hunger, fight inequality and conquer climate change over the next 15 years.

Martijn Lampert, Motivaction’s research director, said the most optimistic responses to the survey had come from emerging economies like China, India and Indonesia, where improvements in poverty rates had been seen first-hand.

For example, 50 percent of Chinese respondents correctly said extreme poverty had been cut in half, compared with just eight percent of Germans and Americans.

“If you look at the western industrialised world, the figures are very low. So one of our conclusions is: if you don’t see it happen, you don’t believe it,” Lampert said.

“(This result) points to a fundamental misunderstanding and missed opportunity for taking poverty eradication to the next level.”