Household income in South Korea rose by the most in nine years as employment neared to a perfect level, data by the finance ministry showed Friday.

Average monthly household income rose 6.1 percent from a year earlier to 4,077,000 won (3,751 U.S. dollars) in 2012, the largest gain since 2003, according to the Ministry of Strategy and Finance. Real household income after accounting for inflation increased 3.8 percent.

The increase came as the country's unemployment rate neared to a full employment level. After peaking at 4.2 percent in February 2012, the jobless rate has trended down to 2.9 percent at the last month of 2012.

Monthly expenditure by households expanded 3.3 percent to 3,217, 000 won last year, rising slower than income. The ratio of household surplus to disposable income jumped 18.4 percent, the highest since 2003.

Consumption expenditure rose 2.7 percent in 2012 after expanding 4.6 percent in the prior year as the South Korean economy rose at the slowest pace last year since the global financial crisis.

Non-consumption expenditure, which includes tax and pensions, rose 5.1 percent last year. Among items, interest payments increased at a slower pace compared with the prior year amid lower policy rates. Bank of Korea (BOK) cut its benchmark seven-day repurchase rate by 25 basis points in July and October each last year.