In recent years, as China's exports have grown rapidly, and the country is registering increasingly larger surpluses on the current account (an estimated $140 billion this year), it has faced a lot of pressure for a "more flexible" exchange rate regime.

Instead of openly calling for an up valuation of the currency, the politically correct euphemism is to use the term "more flexible exchange rate".

After holding on to a steady Yuan-Dollar exchange rate for more than a decade, China has engineered a modest appreciation (5.4 per cent) over the last year and a half. China's exchange rate policy is clearly rooted in the need to create manufacturing employment.

China needs to create at least 25 million non-agricultural jobs a year, considering the number of new entrants in the job market, as also the vast immigration from rural to urban areas. Most of these would have to be in the manufacturing industry, and its global competitiveness is, therefore, of crucial importance.

Hence, the undervalued Yuan. Indeed, for many years, the Yuan's fall in real effective terms was even more than in nominal effective terms, because China has had lower inflation than the US for nine years! This is remarkable at a time of surpluses on current account and huge capital inflows (in theory, both generate inflation pressures), resulting into reserves accumulation of a trillion dollars.

One advantage China has in sterilising the excess money supply is that domestic interest rates are lower than the Dollar or Euro interest rates: this means that there are financial gains to the central bank in sterilising the growth in money supply.

China is not only keeping domestic inflation low but, as a low-cost manufacturer, is a major contributor to keeping global inflation low despite the very high commodity prices of recent years.

But there is also a major risk in the reserve accumulation. As I have argued earlier also in this column, given the huge deficit on current account in the US, the possibility of a sharp fall of the Dollar can hardly be ruled out. Indeed, diversification of Chinese reserves into other currencies (as Russia, Switzerland, Italy and the UAE are already doing) could itself trigger such a fall: it is Chinese investments in the US treasury market that keep the dollar from falling and the yield curve flat to negative.

On the other hand, should the Yuan appreciate against the Dollar, there would be huge paper losses for the central bank as Dollar assets become worth less in Yuan terms. Assuming that, currently, 70 per cent of the reserves are in Dollar assets, even a 5 per cent Yuan appreciation against the Dollar would lead to a translation loss of something like 250 billion Yuan!

Clearly, the authorities are treading on delicate ground trying to balance the needs of the real economy with the possibility of large paper/financial losses if and when the Yuan is forced to appreciate in Dollar terms.

Arguably, the root cause of the large and increasing surpluses China is registering on the current account, is the savings-investment imbalance.

Despite huge investments, the savings rate is so high, above 50 per cent of GDP, that the excess savings result into a surplus on the current account. Interestingly, the household sector savings in China as a percentage of GDP are actually less than in India - this, despite the fact that personal consumption in China per capita is only about 70 per cent higher than in India, while per capita incomes are 2.5 times as large.

The real cause of excess savings is the corporate sector: the corporate sector's savings amount to as much as 30 per cent of GDP, with retained earnings alone contributing two-thirds of that.

One reason, it seems, is that Chinese companies do not distribute dividends. At the macro level, one way of reducing the excess savings and the politically sensitive surplus on current account, is to get the public sector companies to distribute dividends, and spend the money on needed social services like health care, higher old age pensions, and so on.

Sooner or later, we should see some movement in this direction even as the Yuan gradually appreciates. Incidentally, the non-deliverable forwards market is factoring a Yuan rise of just about 3 per cent over the next 12 months.

To my mind, one point on which we need to learn from China is the focus on the real, job-creating economy rather than philosophical arguments about market versus managed exchange rate, the cost of sterilisation, and so on. On the second issue, what we often seem to overlook is that the cost to the real economy of an appreciating currency (jobs uncreated or lost, business profitability, forgone GDP growth, and so on) can be far, far bigger than the financial cost of sterilisation.

To be sure, these costs are not as easy to calculate as the cost of sterilisation - but are, nevertheless, as concrete and perhaps even more important.