过去几个月中国的股市动荡和人民币小幅贬值，使得金融圈人士注意到中国经济的疲弱。他们自然要问，中国经济疲弱将对世界其他地区产生何种影响。答案是，影响甚微，最重要的原因在于，至少4年里中国没有对全球经济真正做出贡献。
认为中国经济疲弱对世界经济构成威胁的观点，融合了大量的错误观念。第一个错误观念是，这种疲弱是个新现象。实际上，当初的中国股市攀升和人民币升值，才多少出人意料；如果要说什么的话，那就是注定发生的局部调整来得太晚了。
中国经济开始走弱不迟于2008年，很可能还更早。始于2009年末并延续至2010年的一轮暂时上行，源于一场不可持续的、不明智的、前所未有的债务爆炸。从2011年开始，世界经济的起伏便不再是由于中国经济的起伏了——中国经济表现的趋势是一路下行。
想要看出这一点，就有必要更精确地理解“经济”这个术语。经济增长可以理解为经通胀调整的（实际）个人收入的增长。长期以来，中国以低成本生产压低通胀，对全球实际个人收入增长做出了贡献。10年前，这是一个非常重要的作用，因为若没有中国的低成本生产，全球通胀水平会高出很多。
不过，如今世界面临通缩压力，而中国增添了额外、甚至过大的通缩压力。另外，鉴于中国仍是一个主要的竞争性生产大国，并且目前没有能力推高大宗商品价格，我们很难看出，中国如何能够对提高海外的名义收入做出净贡献。
当然，讨论经济问题的标准办法是使用国内生产总值(GDP)。大多数评论员使用GDP和“经济”时，两者是可以相互替换的。这是一个明显的误导性错误。在1月中旬的时候，GDP很小，经济却不小。人均GDP没有价值——不然尝试把它花掉试试。
GDP确实使中国显得非常重要。国际货币基金组织(IMF)经常把中国列为对全球GDP增长贡献最大的国家。但
IMF所说的充其量是一种很奇怪意义上的贡献者。如果中国官方统计数据准确的话，中国提高了全球GDP增长率的平均值。而如果北京方面承认GDP增长率不是7%，而是比如说4%的话，那么全球GDP增长率均值将会下降。
简单说，谁会在意呢？即便中国GDP增速下跌拉低全球均值，世界其他地区也没有变化。这并非任何真正意义上的全球衰退。
更重要的是，中国并未对世界其他地区的GDP做出贡献。即便中国确实在对全球经济做出贡献，它也同时在减少其他地区的GDP。这是因为，贸易顺差（净出口）在GDP中被计为正数，而贸易逆差被计为负数。以这种方式对待贸易并无太大意义，但那些用GDP突出中国对世界重要性的人，受到GDP定义的束缚。
去年，中国的官方贸易顺差——巨大的商品贸易顺差和不低的服务贸易逆差之和——约为3800亿美元。这就使世界其他地区的GDP减少了3800亿美元。中国过去10年都出现高额贸易顺差，每年都减少、而不是增加世界其他地区的GDP。
中国GDP增长率下降本身对其他地区并不产生丝毫意义。对GDP重要的是贸易顺差的规模。如果中国贸易顺差上升，那么世界其他地区GDP将相应减少（其他所有条件不变的话）。在这种情况下，贸易顺差也是表明中国对世界真实影响的一个合理指标。中国贸易顺差上升表明，中国正在压低全球价格，加剧既有通缩局面。
GDP常常是不重要的，而中国公布的GDP尤其不重要。想要评估中国对世界经济的影响，请忽略GDP，从贸易着手。（中国进出口网）
Stock market volatility and a small currency devaluation have in the past few months caused the financial community to take note of Chinese economic weakness. A natural question is what effect this weakness will have on the rest of the world. The answer is very little, with most important reason being that China has not truly contributed to the global economy for at least four years.
The idea that Chinese weakness threatens the world economy melds a number of misconceptions. The first is that the weakness is a new phenomenon. It was actually the initial stock market climb and a rising renminbi that were somewhat surprising; the ensuring partial corrections were late in coming, if anything.
China’s economy began weakening no later than 2008, and probably before. A temporary upswing starting in late 2009 and continuing into 2010 was due to an unsustainable, unwise, and unprecedented explosion in debt. From 2011 on, ups and downs in the global economy have not been due to ups and downs in China – the trend in Chinese performance has been invariably down.
To see this, it’s necessary to be more precise about the term “economy.” Economic growth can be understood as growth in inflation-adjusted (real) personal income. China has long contributed to global growth in real personal income by dampening inflation with low-cost production. A decade ago, this was an important role because inflation could have been considerably higher without low-cost Chinese production.
Now, however, the world faces deflationary pressure and China’s deflationary contribution is extraneous, even excessive. Further, it is hard to see how China can be contributing on a net basis to higher nominal incomes overseas given that it remains a major production competitor and not presently capable of driving commodity prices higher.
Of course, the standard way of discussing the economy is to use gross domestic product (GDP). Most commentators use GDP and “the economy” interchangeably. This is a clear and misleading error. The economy is not tiny in the middle of January, as GDP is. GDP per person has no value – just try to spend it.
GDP does make China look very important. The IMF routinely ranks China as the leading contributor to global GDP growth. At best, this is a very strange notion of a contributor. China raises the global GDP growth average, if its official statistics are accurate. If Beijing were ever to acknowledge that GDP growth was, say, four percent instead of seven, average global GDP growth would fall.
To put it succinctly: who cares? In a situation wher a Chinese GDP growth dro lowers the world average, the rest of the world has not changed. This is not a global recession in any meaningful sense.
More important, China does not contribute to the rest of the world’s GDP. It detracts from it, even when China is in fact contributing to the global economy. This is because a trade surplus (net exports) is counted as a positive in GDP and a deficit is counted as a negative. Treating trade in this way does not make much sense but those using GDP to heighten China’s importance to the world are stuck with its definition.
China’s official trade surplus – its huge goods surplus and sizable services deficit combined –was roughly $180bn last year. This constitutes $180bn subtracted from the rest of the world’s GDP. China has been running large trade surpluses for a decade, each and every year subtracting from the rest of the world’s GDP, not contributing.
Slower Chinese GDP growth would, in itself, mean nothing at all to anyone outside the country. What matters to GDP is the size of the trade surplus. If it rises, then rest-of-world GDP falls by that amount (everything else constant). In this case, the trade surplus is also a reasonable representative for China’s true impact on the world. A rising surplus says China is pushing down prices around, intensifying existing deflation.
It is often the case that GDP does not matter and it is typically the case that China’s claimed GDP does not matter. To evaluate China’s impact on the world economy, ignore GDP and start with trade.
