OUR discussion is concerned in how to achieve a balance between yin and yang acceptable in the urbanization of Shanghai. The concerns are two-fold and are becoming pressing.

One, urbanization is slowing down, and the gear is shifted from extensive scale yang toward intensive quality yin. Urbanization in China is now 46 percent, up from as low as over 20 percent just 30 years ago. The task at hand is to improve the yin sphere - quality of services and rules of governance, which will certainly be more challenging.

Two, the supply of female labor is lagging behind that of male labor, with the gap widening. This imbalance of yin and yang will have profoundly undesirable impacts.

In our discussion previously in this column on the changes in the required skill structure of American labor, we drew the conclusion that the contemporary urban development demands more industries and skills of the yin type, in terms of both quantity and quality.

In contrast, developing regions in China prefer boys to girls as a deep-rooted tradition. Consequently, the gender ratio of newly born babies there is distorted to be 100 girls for every 120 boys, a substantial deviation from the natural norm: the yin and yang should be 100:106. The ratio in some regions could be seriously biased to as far as 100:129.

One of the negative consequences is boys outnumbering girls by 25 million, a tremendous gap not easily absorbed. The problems could extend far beyond production and employment. Without suitable women to match them, men cannot get married and form families.

The leftover men, or guanggun (its Chinese nickname, with the meaning "a branch without leaves and fruits"), will inevitably become embittered. A massive number of leftover men will be a big factor in unrest, endangering the stability and order of communities, as witnessed by various incidents in various countries.

Take South Korea for instance. The TFR of the South Korean population has declined to 1.2, a level worse than France. This trend, to the horror of the entire nation, is tough to alter. TFR is primarily dependent on the female - their base of proportion, and their intention to bear and raise kids.

On individual willingness, South Korean women, sharing the fruits achieved in remarkable economic and social progresses, have been experiencing tremendous improvement in income and education; they consequently tend to postpone marriage age or opt not to marry at all, and choose in general to have fewer children.

Women in South Korea are also under-proportionate in the gender structure, owing to a tradition of male preference. Thanks to the rise in women's social status, the once-serious bias in favor of boys is now being corrected; however, the momentum carries on.

The following set of statistics is revealing: the yin yang ratio of the first baby in South Korean households: 100:104, very normal. But the ratio of 100:113 for the second baby, 100:185 for the third baby, and 100:209 for the fourth baby are way too distorted. Human interference is undeniable.

Correcting the population decline and yin yang structure distortion in South Korea are therefore formidable if not insurmountable obstacles.

On the other hand, the correction is a must-do. After all, economic growth is dependent upon demographic change. The impacts of population changes and age and sex structures can be accurately calculated. For example, the Tokyo real estate market's continuous decline is determined more than anything else by the population shrinking and aging in Japan.

Hats off to girls

If we could gain some insights from the above observations and others' failures, I tend to believe that career development for females will be better in Shanghai; and women will enjoy favored opportunities better than those available to men from a nationwide perspective.

As yin is getting the upper hand, if a married couple could choose the gender of next baby, they should go with a girl and not a boy, because girls' future is becoming brighter and more rewarding; this is in opposition to the traditional bias.

From an individual perspective, girls will enjoy more leverage to choose.

If Ms Xu Jinglei (a movie star) remains unmarried (see yesterday's article), it must be her choice, a reflection of her independence and higher social status, and by no means the result of being left over.

It might be a waste since her good genes would regretfully be terminated, fruitless. The true leftovers in view of current imbalance of yin and yang, the table has been turned on men already.

From a family perspective, people will lament that their sons will have difficulties entering marriage. You may have to help your son pay for a house for a daughter-in-law. Occasionally even a house won't do the job, and your son might have to be adopted by in-law's family and have the grandchildren named after theirs. Too bad.

From a policy perspective, Shanghai should first of all avoid the policy Guangdong Province is pursuing: in an attempt to relax the one-child restriction, Guangdong allows these families a second chance if their first born is a girl.

Shanghai would do much better to adopt a policy of two children without the gender preference. Two girls will turn out to be better than two boys, if the combination of one yin and one yang does not work out.

Secondly, Shanghai had better start collecting market data for the skills structure. With the relative proportions of yin and yang types of personnel better understood, long-term urban planning can mesh with market demand and growth needs.

In the United States there are some good practices in this respect. Based on Bureau of Labor Statistics data, American cities normally provide information on distinct skills, whether of yin type or yang type, like physical, analytic, and social-related skills, their average compensations and relative market demands for them in the city. This information can facilitate better decisions for various stakeholders.

This is the second and final part of the author's article on the yin and yang of a city. The author is Professor of Business at California State University at Long Beach. Born in Shanghai, he studied in the US in the early 1980s and there received a master's in economics and Phd in management. He served as general manager of investment banking and the IPO office of the China Construction Bank. He was CIO of the Shenzhen Development Bank. He was a Fulbright scholar and has received numerous awards in China. He is the author of 14 books in Chinese and writes an influential newspaper column. He lives in Los Angeles. (brucesunchina@gmail.com)