Department stores' hottest item this year: Their own shares

South Korea's department store operators have become some of the market's standout performers, as luxury shoppers and foreign tourists return in force, turning the once-stagnant sector into an investor favorite.

Over the past six months, shares of Shinsegae, Lotte Shopping and Hyundai Department Store have surged 166.5 percent, 146.1 percent and 97.2 percent, respectively, as of Monday's close.

Shinsegae stands apart, up more than 300 percent over the past year, far outpacing its peers.

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