In a trend fraught with troubling political and social implications, China will soon find itself with a marriage-age population remarkably out of balance, with about 23 million more young men than women available for them to marry in this decade and the next — what demographers term a "marriage squeeze."
This impending surplus of unattached young men could be a driving force behind increased crime, explosive epidemics of HIV and other sexually transmitted diseases, and even international threats to the security of other nations. Yet the Chinese government has done little to address its demographic destiny.
The coming squeeze is largely the legacy of the government's one-child policy, along with societal modernization. As a result, the nation's fertility rate has fallen dramatically, from around 6 children per woman in the 1960s to around 1.7 currently. But the society's strong cultural preference for sons has not changed. In recent decades, ready access to ultrasound technology has enabled parents to learn the sex of their unborn children and has led to widespread female-specific abortion.
The demographic consequence is now apparent. Most societies exhibit biologically natural sex ratios at birth of around 105 baby boys born for every 100 baby girls, yielding roughly equal numbers of prospective brides and grooms as generations reach marriageable age. This normal pattern emerges where human interventions don't disturb biology.
But China has departed markedly from this natural pattern since the 1980s. Its sex ratio at birth has hovered between 115 and 120 baby boys for every 100 baby girls in recent years, a level that renders roughly one of every eight men in a generation "surplus." Many Chinese refer to the surplus boys as guang gun (bare branches).
Past societies with large numbers of unattached men have on occasion turned to a more authoritarian political system, perceiving threats of violence. Such societies have also sought to harness their surplus of men by recruiting excess males into military occupations, pursuing expansionist policies aimed at developing unexplored territories or colonizing neighboring ones.
The tensions associated with so many bachelors in China's big cities might tempt its future leaders to mobilize this excess manpower and go pick a fight, or invade another country. China is already co-opting poor unmarried young men into the People's Liberation Army and the paramilitary People's Armed Police.
No less disquieting are the social dynamics accompanying a severe marriage squeeze. In all likelihood, millions of young, poor Chinese bachelors never will marry. Many will migrate from rural areas to urban destinations, patronizing prostitutes there. In doing so, these unattached men could turn China's HIV epidemic — now confined to certain high-risk populations — into a more generalized one by creating "bridging" populations from high- to low-risk individuals. Such male bridging populations have fueled HIV epidemics in Cambodia and sub-Saharan Africa.
China's legal marriage age — 22 years for men, 20 for women — means that more than 23.5 million young men (by our estimate) will be unable to find Chinese wives during the period from 2000 to 2021, owing to the inadequate supply of Chinese women in the marriage market. Neither a spontaneous shift toward a later average age at first marriage nor lax enforcement on the supply side to allow teenage brides would substantially lessen this market imbalance.
Although the 23 million-plus surplus of boys exceeds the entire population of most countries, it represents but a tiny fraction of all 1.3 billion Chinese. However, these millions of "bare branches" will be concentrated in a generation born over a short 20-year period and living mostly in the cities of a largely rural China.
The surplus of boys and shortage of girls "made in China" could soon become not just a concern for China, but for the world.
Dudley L. Poston is a professor of sociology at Texas A&M University. Peter A. Morrison is a demographer with RAND Corp.
This commentary originally appeared in International Herald Tribune on September 14, 2005. Commentary gives RAND researchers a platform to convey insights based on their professional expertise and often on their peer-reviewed research and analysis.