Savers may be helping to drive down the value of the yen as they take advantage of changes in the rules for tax-free accounts and bet heavily on foreign funds.

So far this year, these individuals have been pouring about ¥1 trillion ($6.2 billion) a month into international investments, which analysts say might have added ¥0.5 to ¥1 per dollar to the exchange rate every month.

The yen is currently trading at about ¥161 to the dollar and remains on the weak side as the Bank of Japan keeps rates low and continues to waver on the reduction of bond purchases. The currency is down more than 15% over the past year.