IN PI VILLAGE, on the outskirts of Beijing, a man in his late 50s who gives his name as Ren is mixing cement for a new apartment building. As he shovels, he gives an account of bride-price inflation. When he married, his parents gave his wife 800 yuan, which seemed like a lot. Twelve years ago one of Mr Ren’s sons married. His bride got 8,000 yuan. Recently another son married, and Mr Ren had to stump up 100,000 yuan ($15,000). He is likely to be mixing cement well into his 60s.

Like India, most of China is patrilocal: in theory, at least, a married woman moves into her husband’s home and looks after his parents. Also like India, China has a deep cultural preference for boys. But whereas India has dowries, China has bride prices. The groom’s parents, not the bride’s, are expected to pay for the wedding and give money and property to the couple. These bride prices have shot up, bending the country’s society and economy out of shape.

The cause, as Mr Ren explains, is a shortage of women. Without human intervention, about 105 boys will be born for every 100 girls: boys and men are slightly more likely to die, so by the time they reach reproductive age the number of men and women should be roughly equal. But many Chinese couples have tipped the scales. Driven partly by China’s now-abandoned one-child policy, they have used ultrasound scans to determine the sex of fetuses and then aborted some of the girls. By 2010 there were 119 boys under five years old for every 100 girls. Two demographers, John Bongaarts and Christophe Guilmoto, estimate that China is missing more than 60m women and girls.

In the province of Shandong, in eastern China, the child sex ratio skewed early and drastically. It was highly unbalanced by 1990, and by 2010 had reached 123:100. Moreover, not all Shandong girls hang around awaiting marriage proposals from local boys. The province lies between Beijing and Shanghai, so it is easy for the province’s young women—said to be unusually tall and beautiful—to migrate to the great metropolises in search of work and boyfriends. The result is a severe shortage, and bride prices that are barmy even by Chinese standards.

In Zhongdenglou, a tidy village in western Shandong, 30-year-old Deng Zhikuan runs a grocery store. When he married, ten years ago, bride prices in the village were between 2,000 and 3,000 yuan. Now they run between 200,000 and 300,000 yuan, although Mr Deng hears that as much as 500,000 has been handed over (50,000 yuan would be a respectable annual salary thereabouts).

Past it at 25

Other villagers give similar figures. It is a buyer’s market, complains Qiang Lizhi, a newly married man who runs a café nearby. A 47-year-old man, Deng Xinling, says that men are now considered shopworn if they are unmarried at 25. By contrast, no woman is thought too old to marry; even widows have no difficulty in finding husbands.

China’s growing sex imbalance is driving boys’ parents to desperate lengths. Some add another storey to their houses, not because they need the space but because a woman might be impressed. They give money to their sons to buy gold jewellery and pay for extravagant wedding photo shoots. They start saving early, then go into debt. China has a sky-high household saving rate: couples squirrel away 38% of disposable income, compared with 10% in notoriously frugal Germany. Two academics, Shang-Jin Wei and Xiaobo Zhang, estimate that half the increase in China’s saving rate between 1990 and 2007 can be attributed to the rising cost of marriage in a society with too many men.