Deposit your money at a bank in northern Japan and you could get more than interest payments. You might end up getting married.

This weekend, 184 depositors at Tsuruoka Shinkin Bank — single men and women with an average age of 32 — are invited to mingle in front of a tank of glowing jellyfish at a local aquarium for the lender's first "konkatsu" (marriage-hunting) party.

The bank in Yamagata Prefecture, 500 km north of Tokyo, is facing a decline in population afflicting rural communities across Japan. The challenge is acute for "shinkin" banks — cooperatives whose members are local residents and small businesses.