South Korea's state-run statistics office said Friday it has revised the composition and calculation of its consumer price index in a bid to better reflect price trends of key items.

Statistics Korea said it changed the base year for the calculation of the index to 2015 from the previous 2010, and the index's composition.

The revision, made every five years to maintain the accuracy of the index, is applied retroactively to data compiled since January 2016, the agency said.

According to the statistics office, prices of 18 new items, including blueberries, pasta noodles, electric cookers, health equipment, rental fees of massage chairs and health insurance premiums, were added to the index.

"We newly included such items in the survey basket in accordance with a change in consumption patterns," said Woo Young-jae, director of the price statistics division at the statistical bureau.

"This time, we've included many health-related products as a growing number of people have interest in health amid the rapid aging (of the country's population)."

The agency said prices of magazines, paper dictionaries, ketchup and bell peppers were excluded from the index list.

Under the revised terms, the country's consumer price index rose 0.9 percent on-year in the first 11 months of the year, compared with the 1 percent increase tallied on a 2010 basis, according to the agency.

South Korea's inflation rate has been subdued for years due to fast-falling oil prices and a global economic slowdown, with the inflation rate having hovered around 1 percent, far lower than the target inflation of 2 percent.

In November, consumer prices grew 1.3 percent from a year earlier, unchanging from the previous month, staying over the 1 percent level for three straight months.

The figure had remained less than 1 percent between May and August, fueling concerns over deflation in the country. (Yonhap)