Yen for yen obstructs BOJ's inflation goals

Morgan Stanley analysts say central banks bought $45 billion worth of currency in second half of 2014

Bank of Japan Governor Haruhiko Kuroda can count yen purchases by global peers among the obstacles to achieving his 2 percent inflation target.

Central banks added to their yen holdings in order to keep the ratio of Japan's currency constant in dollar terms as it tumbled against the greenback at the end of 2014, according to analysis of International Monetary Fund data by banks including Morgan Stanley and JPMorgan Chase & Co. The yen's share of global reserves is about 4 percent in terms of the dollar.