Samsung Electronics suffered a 24.6 percent decline in its quarterly operating income, from 9.53 trillion won in the second quarter of 2013 to 7.19 trillion won in the second quarter this year. The deep cut in its operating income came as a shock to industry analysts, with earlier earnings forecasts by 26 brokerages having averaged 8.71 trillion won.

Hyundai Motor Group fared better. Yet, its second-quarter operating income plummeted almost 20 percent to 2.86 trillion won. The sharp fall came despite a 4 percent increase in its vehicle sales.

Samsung and Hyundai are among the large number of blue chips that suffered declines in their operating incomes or other losses in the second quarter. They say the strengthening Korean currency is the main culprit.

The won, they say, has strengthened to a point where the exchange rate is no longer tolerable. It goes without saying that their complaints about the won’s rapid gain against the U.S. dollar should be taken with a grain of salt. But the average exchange rate in the first half of this year dropped 50 won from a year ago, with the rate being inversely proportional to the won’s value.

The exchange rate is now hovering around the 1,025 won level, well below what they call the break-even exchange rate, which, according to a recent survey by the Federation of Korean industries, stands at 1,052 won per dollar. To their chagrin, however, the worst is yet to come, with great pressure being exerted on the won to strengthen further.

Earlier in the week, the International Monetary Fund called on the Korean government to refrain from intervening in the foreign exchange market and allow the won to be freely traded. The IMF suspects the government makes dollar purchases frequently to keep the won weak, instead of limiting its occasional intervention to smoothening volatility, as it claims.

The IMF found fault with Korea’s continued buildup of foreign reserves, which it apparently believes are more than enough. Its foreign reserves stood at $366.5 billion at the end of the first half.

The IMF’s grudge against Korea’s foreign exchange policy followed an earlier report that its balance of international payments produced the largest-ever surplus in the first half of this year ―- $39.2 billion. If this trend continues, the Bank of Korea said, the year-end surplus will top $84 billion.

Korean export companies should be reminded that there is a limit to what the Korean government can do to shield them from a strengthening won. The United States and Korea’s other trade partners, who share the IMF’s complaint, are pushing for the won’s rapid gain.

What corporations need to do is to comply with the government request that they spend more on capital goods from abroad and thus help reduce the nation’s current account surplus. That is the least they can do to slow down the won’s appreciation.

Moreover, the IMF is urging the Korean government to boost aggregate demand by encouraging corporations to increase their investments and consumers to loosen their purse strings. Sitting on huge export earnings will be of little help to them or to the nation.