South Koreans worked 2,163 hours in average last year, ranking second among the 34 member states of the Organization for Economic Cooperation and Development, according to an OECD report on Monday.

Ahead of Korea was Mexico, which ranked at No. 1 with 2,237 hours.

Korea previously held the No. 1 position for eight consecutive years from 2000-2007, but slid a notch in 2008.

The fall was largely attributed to the five-day workweek system that was introduced in 2004, according to industry sources. An increase in part-time workers also caused the working hours to fall, they said.

Koreans’ average working hours, however, still stood at 1.3 times the OECD average of 1,770 hours.