Yen, bond yield plunge, stocks soar after BOJ maintains policy

The yen briefly plunged to the 131 level against the U.S. dollar Wednesday in Tokyo after the Bank of Japan defied market pressure and maintained its ultraeasy monetary policy, with stocks soaring and the key government bond yield tumbling.

The yield on the benchmark 10-year government bond dropped to 0.360 percent, its lowest since late December, returning to within the upper limit of 0.500 percent set by the BOJ last month. The yield had risen above the bank’s ceiling for the fourth straight day earlier in the day.

The 225-issue Nikkei Stock Average ended up 652.44 points, or 2.50 percent, f...