YOKOTA, Shimane Pref. -- The curator of this town's abacus museum must have a sense of black humor to have included one of the first Sharp calculators in the display.

After all, Yokota's economy was built on the "soroban" -- or Japanese abacus -- and production has been on a long tumble since the price of pocket electronic calculators began falling at the end of the 1970s.

Twenty abacus factories in Yokota made around 1.2 million boards in 1978 -- the town's peak production year. By last year, that figure had dwindled to 250,000 from four factories.