Wages have increased far more slowly than corporate profits, which is cited as one of the reasons for the slowdown in consumer spending.

The Bank of Korea in a report on Monday said wages increased 11.7 percent on average per year in the 1990s, just 1.1 percentage points lower than the annual growth in corporate profits. But since 2000, wages have increased only 7.2 percent a year on average, a full three percentage points behind corporate profit growth.

The share of the nation's gross national income that goes to households has therefore dwindled. As of 2011, household income accounted for just 61.6 percent of GNI, down a whopping 8.9 percentage points since 1995.

The trend is global, but much more marked in Korea than elsewhere. OECD member countries saw an average decline of 4.1 percentage points in households’ share of GNI to 69 percent.

The slowdown in household income translates into lackluster consumption. Consumer spending accounts for 59.8 percent of Korea's GDP as of 2011, far below the average 68.5 percent in the OECD. "Households spend almost 98 percent of their incomes on private consumption, but the overall amount is small due to households' paltry share of GNI," the BOK said.