The combined domestic market share of Hyundai Motor Co. and its affiliate Kia Motors Corp. dropped to an all-time low in October due largely to a decline in output caused by labor strikes and a rise in the sales of foreign vehicles here, industry data showed Friday.

According to the data, the corporate duo's domestic market share stood at 58.9 percent last month, dipping to below the 60-percent threshold for the first time.

Last month, a total of 148,078 vehicles were sold in South Korea, with the combined sales by the two reaching 87,220, according to the data.

GM Korea, the South Korean unit of General Motors Co., came in second with 11.3 percent, followed by Renault Samsung Motors Co., the local unit of French automaker Renault S.A., with 9 percent and Ssangyong Motor Co. with 6.4 percent.

The figures include commercial vehicles sold by the automakers.

Foreign carmakers held a combined 13.9 percent last month, the data showed.

Last year, Hyundai and Kia saw their domestic market share stay below the 70 percent mark for the second straight year, affected by the marked advances of foreign brands and intense competition from other smaller local rivals.

Hyundai Motor and Kia Motors commanded 67.7 percent of domestic car sales last year, compared with 69.3 percent a year earlier.

Their market share peaked at 80 percent in 2009 before falling to 74.6 percent in 2012 and 71.5 percent in 2013.

Their domestic presence shrank on growing challenges from foreign brands and other smaller rivals.

Sales of imported vehicles jumped 24.2 percent on-year to a record 243,900 units last year, data showed. (Yonhap)