More than 2,300 companies in Japan have introduced 401(k)-style pension plans, marking a 1.6-fold increase over the past six months, according to government data released Monday.

The number of companies adopting 401(k)-style pension plans, or defined-contribution pension schemes whose benefits hinge on investment performance, totaled 2,379 as of the end of March, up from 1,522 six months earlier, the Health, Labor and Welfare Ministry said.

Despite the sharp increase, only about 700,000 people, or a little more than 2 percent, of some 30 million company employees in the nation are covered by these pension schemes.

Defined-contribution pension plans, in contrast with conventional defined-benefit schemes, were introduced in Japan in October 2001.