IN THE 1990s China had one of the highest suicide rates in the world. Young rural women in particular were killing themselves at an alarming rate. In recent years, however, China’s suicides have declined to among the lowest rates in the world.

In 2002 the Lancet, a British medical journal, said there were 23.2 suicides per 100,000 people annually from 1995 to 1999. This year a report by a group of researchers from the University of Hong Kong found that had declined to an average annual rate of 9.8 per 100,000 for the years 2009-11, a 58% drop.

Paul Yip, director of the Centre for Suicide Research and Prevention at the University of Hong Kong and a co-author of the recent study, says no country has ever achieved such a rapid decline in suicides. And yet, experts say, China has done it without a significant improvement in mental-health services—and without any national publicity effort to lower suicides.

The most dramatic shift has been in the figures for rural women under 35. Their suicide rate appears to have dropped by as much as 90%. The Lancet study in 2002 estimated 37.8 per 100,000 of this age group committed suicide annually in 1995-99. The new study says this declined to just over three per 100,000 in 2011. Another study of suicides, covering 20 years in one province, Shandong, found a decline of 95% among rural women under 35, to 2.6 suicides per 100,000 in 2010—and a 68% drop in suicides among all rural women.

Scholars suspect that the number of suicides is underreported in official figures (the official suicide rate nationally was 6.9 per 100,000 in 2012) and they make adjustments for that in their calculations. But in several studies, as well as in official data, the long-term decline in suicides has been marked across the spectrum, in rural and urban areas and among men and women from almost all age groups. The only notable exception is the suicide rate among the elderly, which declined overall but has crept back up in recent years, a worrying trend in a rapidly ageing society.

Two intertwined social forces are driving the reduction: migration and the rise of an urban middle class. Moving to the cities to work, even if to be treated as second-class citizens when they get there, has been the salvation of many rural young women, liberating them from parental pressures, bad marriages, overbearing mothers-in-law and other stresses of poor, rural life. Migrants have also distanced themselves from the easiest form of rural suicide, swallowing pesticides, the chosen method in nearly 60% of rural cases, and often done impulsively. The reduction in toxicity of pesticides has helped as well.

Jing Jun, a sociologist at Tsinghua University in Beijing, notes that the increase in migration to the cities fits with the decline in rural suicides (see chart). Since rural dwellers accounted for most suicides, so the national rate has fallen, too. In 20 years, as the population went from mostly rural to more than half urban, the official national suicide rate dropped by 63%. Suicides among urban residents are also dropping, suggesting other causes, too. Chinese newspapers frequently carry dramatic photos of suicidal people being rescued from window ledges and rooftops (like the woman in our picture). But the University of Hong Kong researchers found that urban suicides had dropped to 5.3 per 100,000 between 2002 and 2011, a fall of 59%. The simplest explanation is that, in spite of concerns about pollution, food safety and property prices, living standards and general satisfaction with urban life have gone up. Mr Jing also believes that, as in the countryside, the atomisation of extended families has reduced the family conflicts that can lead to suicides. Mr Yip and his fellow researchers wonder if this goes against a popular theory, based on the thinking of Emile Durkheim, a 19th-century French sociologist, that urbanisation, modernisation and socioeconomic gains lead to increased social alienation and a higher suicide rate. Some data support this view in the richer developed world, where suicide rates have been rising recently. The estimated global average has increased from 11.6 to as much as 14 per 100,000 since 2008. And China’s rich neighbours have significantly higher rates—South Korea’s in 2012 was 28.1 per 100,000, Japan’s was more than 21. Yet China may be hitting a worrisome turning point as it ages and becomes more wealthy. Suicides rose slightly after the 2008 financial crisis, and may continue to do so if the economy slows more dramatically. The forces that shaped suicide’s decline in China—migration and rising urban living standards—are losing steam as well.

Most worrying is that suicides remain high among the fastest-growing segment of society, the elderly, who kill themselves at rates ranging from 9.9 per 100,000 urban men aged 65-69 to 41.7 per 100,000 rural men aged 70-74. Suicide rates among the elderly generally dropped overall into the middle of the past decade—declining more in the cities than in the countryside—but the rates have been holding steady or resurging since 2008.

The urbanisation and atomisation of the extended family, which led to a decline in suicides among younger generations, have left the elderly with fewer caretakers in the countryside and with few familiar faces in apartment blocks in the cities. The one-child policy has compounded this effect and will only make the burden heavier for the elderly and their children, just as the stresses of modern life are becoming more pronounced. Twenty years from now, the story of China’s suicide rate could be grimmer than it is today. But rates seem unlikely to return to the levels of the 1990s.