A newly published Bank of Korea report indicates the country's labor market is becoming increasingly polarized and labor mobility is getting more difficult.

It says as of 2014, workers at large companies with 300 or more employees make one-point-seven times the wage of workers at small and medium-sized enterprises. That is up from the one-point-one wage gap in 1980. 

The percentage of workers from a small or mid-sized firm moving to a larger enterprise after a year has dropped from three-point-six percent in 2004 and 2005 to two percent in 2015 and 2016.

The percentage of nonregular workers transitioning to regular positions has also fallen from 15-point-six percent to four-point-nine.