Sales of Korean-made products have risen in domestic duty-free shops to reach 40 percent of all sales, according to data from the Korea Customs Service on Sunday.

Duty-free outlets in Korea saw revenues of 3.74 trillion won ($3.17 billion) in the first third of 2016, marking an 18.1 percent increase from the same period last year. Korean-made products were credited for 42.2 percent of those sales.

The latest numbers show a continued rapid increase in Korean-made products. In 2012, Korean products made up under one-fifth of all duty-free sales. Sales revenue since 2012 has increased by 171.5 percent.

The change has been mainly led by increasing demand from shoppers visiting from China and other countries where Korean dramas and other cultural content are popular.

Although the increase in domestic product sales is a positive phenomenon for duty-free operators, some fear that the rise is dangerously concentrated in certain industries. For instance, Korean cosmetics – which have become hugely popular among Chinese tourists – made up 68 percent of all duty-free Korean product sales.

Earlier this month, the Korea Duty Free Association petitioned the Trade Ministry to change current regulations that do not count duty-free sales as exports.

According to the KDFA, allowing small- to medium-sized brands in duty-free outlets to report their sales as exports would help them to obtain government support as exporting companies. In turn, they would make higher-quality products to ease the duty-free outlets’ dependence on cosmetics sales.

The Trade Ministry has yet to take an official stance on the issue.

By Won Ho-jung (hjwon@heraldcorp.com)