Korea's GDP growth at 5-year high: Key facts

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South Korea's economy grew at its fastest pace in five years in the third quarter, shaking off the blow dealt by the deadly Middle East Respiratory Syndrome (MERS) outbreak earlier in the year.

Gross domestic product (GDP) grew by a seasonally adjusted 1.2 percent in the July to September period over the previous quarter, according to an advance estimate published on Friday. This marks the fastest pace since the second quarter of 2010 and is up sharply from 0.3 percent growth in April-June. In year-on year terms, growth accelerated 2.6 percent, up from 2.2 percent in the previous quarter.

Here's what drove the growth:

Based on expenditure, gross fixed capital formation rose 2.9 percent on quarter, driven by a rise in construction activity. Construction investment grew 4.5 percent, with increases in both building construction and civil engineering. Companies also invested in machinery and equipment, boosting facilities investment.

Private consumption expanded by 1.1 percent on quarter, led by an uptick in spending on both services and durable goods, while government spending rose by 1.9 percent.

"We expect domestic demand to remain the main driver of the recovery, helped by supportive policy measures," Krystal Tan, Asia economist at Capital Economics wrote in a note.

"The BoK [Bank of Korea] has cut its policy rate four times since August 2014, which has in turn supported a pick-up in household credit growth. With inflationary pressures benign, monetary policy will likely remain loose over the next year."

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On top of monetary support, the government has also stepped in with measures to boost the economy. In late July, the parliament passed an 11.5 trillion won ($10.2 billion) supplementary budget to help cope with the economic fallout associated with MERS.

Exports, on the other hand, were a key drag on the economy, reflecting weak external demand, particularly from key trading partner China. Imports meanwhile increased, pinching the net exports component

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Exports contracted 0.2 percent on quarter, with decreases in shipments of LCDs, chemical products and ships.

"The export sector remains a weak spot, but while a strong rebound is unlikely, we expect a modest improvement in external demand, particularly from China, to offer some support in the coming quarters," Tan said.

Nevertheless, Korea's growth bounce back is prompting some economists to take another look their annual growth forecasts.

"We are reviewing our 2.2 percent full-year growth forecast for upward revision," said Prakash Sakpal, economist at ING.

Based on performance by activity, the electricity, gas, and water supply component surged 7.9 percent in the September quarter as the unusually warm weather likely prompted people to crank up their air conditioners, lifting demand for electric power. Agriculture expanded 6.5 percent, having tumbled a whopping 12.2 percent in the previous quarter.

Construction grew by a tidy 5.3 percent as building activity picked up. Services, having not grown at all in the previous quarter due to the MERS outbreak, climbed 1 percent as relieved consumers ate out and shopped more. The country's manufacturing sector only grew a feeble 0.1 percent.