赵永军:“只生一个好”的经济代价

2011年 04月 29日 12:48“只生一个好”的经济代价
评论(23)真的是只生一个好吗？

从中国新的人口普查数据来看，中国推行独生子女政策的经济成本远远高于政府愿意承认的水平。

中国政府声称生育率是1.8，低于保持人口总量稳定所需的2.1。生育率指的是妇女一生中预计所生孩子的平均数量。

但要是政府过于乐观了呢？中国人口学家一直在说，生育率实际上大幅低于官方声称的数值。国家统计局在2010年进行的10年一次的人口普查结果表明，他们的话或许是对的。清华-布鲁金斯公共政策研究中心(Brookings-TsinghuaCenter)驻北京的中国人口学专家王丰说，普查数据说明生育率确实是1.5或更低水平。

1.8和1.5的差别看起来或许并不是那么大。但以中国这么大的人口总数，在经过较长时期过后，生育率的微小差别也会产生深远的影响。据联合国预测，如果生育率确实是一直维持在1.8的水平，那么2030年之前劳动年龄人口将接近10亿。而据美国人口普查局(U.S CensusBureau)预测，1.5的生育率意味着劳动年龄人口将在2015年达到顶峰，到2030年将下降至9.4亿。

世界大型企业研究会(Conference Board)首席经济学家范阿克(Bart vanArk)说，从20世纪70年代末开始改革开放以来的头20年里，劳动人口的增加平均每年为中国经济增速贡献了0.9个百分点。在经济增长加快的同时，劳动力的过剩供给遏制了工资的上涨，并使通胀保持在低水平。在21世纪头10年，消费价格平均每年涨幅只有1.9%。

不管生育率问题上谁对谁错，经济增长都将不再获得劳动力增加带来的正面贡献。在两种预测中，劳动人口总量都已经见顶下跌。2015年过后，如果政府有关劳动人口数量将保持稳定的说法言中了，那么经济增长速度不会受到负面影响。如果人口学家是对的，劳动人口数量的减少就会拖累国内生产总值的增长。

同样重要的是，人口老龄化将需要有更高水平的福利，而新加入劳动人口的人数减少，将开始推高工资、加剧通货膨胀。提高退休年龄或者是采取措施增加劳动参与率会缓解这种冲击，但不可否认的是，人口方面曾经推动中国前进的顺风现在正在往反方向吹。

对于中国经济来说，很可能是“只生一个好、生两个更好”。

Is one really best?

New census data from China suggest theeconomic costs of Beijing's one-child policy are more serious than thegovernment is prepared to acknowledge.

The government claims thefertility rate, the number of children an average woman is expected tohave over the course of her life, is 1.8. That is lower than the 2.1needed to keep a population stable.

But what if the government isbeing optimistic? Chinese demographers have been arguing that thefertility rate actually is considerably lower than official claimssuggest. The results of a decennial population census by the NationalBureau of Statistics in 2010 shows they might be right. Wang Feng, aspecialist on China's demographics at the Brookings-Tsinghua Center inBeijing, says the census data confirm the fertility rate is 1.5 orbelow.

The difference between 1.8 and 1.5 might not seem thatgreat. But with a population as large as China's and over a long timehorizon, the consequences of small differences in the fertility rate arefar reaching. If the fertility rate has been running at 1.8, theworking-age population will be close to a billion through 2030,according to projections by the United Nations. A rate of 1.5 means itpeaks in 2015 and by 2030 is down to 940 million, according toprojections by the U.S Census Bureau.

According to ConferenceBoard chief economist Bart van Ark, an expanding labor force contributedan average 0.9 percentage point annually to China's economic growthduring the first 20 years of the reform era, which started in the late1970s. Even as growth accelerated, a surplus supply of workers keptwages down and inflation low. In the first decade of the 21st century,the annual change in consumer prices averaged just 1.9%.

Whoeveris right about the fertility rate, there will be no more positivecontribution to growth from increases in the labor force. On either setof projections, the size of the labor force already has peaked. After2015, if the government is right that the work force will stay stable,there will be no negative impact on the growth rate. If the demographersare right, a shrinking work force will mean a drag ongross-domestic-product growth.

As important, an aging populationwill require higher levels of welfare payments, and reduced flows intothe labor force will start to bid up wages and push inflation higher. Anincrease in the retirement age or moves to increase labor-forceparticipation would lessen the blow. But the fact remains thatdemographic tailwinds that have propelled China forward are now blowingin the other direction.

For the Chinese economy, it is looking likely that one is good, but two is better.

Tom Orlik