TOKYO (Reuters) – Japan’s central bank saw some sweeping changes in a personnel reshuffle on Monday, including the appointment of its first female executive director in the male-dominated institution.

Tokiko Shimizu, a 55-year-old career central banker, became the first woman to fill one of the Bank of Japan’s six executive director posts in government appointments announced on Monday.

Her appointment to the BOJ’s top bureaucrat post is likely part of the central bank’s efforts to diversify its management.

Just one woman serves in the BOJ’s nine-member board that makes key policy decisions. Takako Masai is a former commercial banker.

Only 13% of senior BOJ managerial posts are filled by women.

While 47% of all BOJ staff are women, the ratio drops to 20% for career and expert positions, according to BOJ data.

The career of Shimizu, currently the BOJ’s branch manager in the central Japan city of Nagoya, included stints at the bank’s financial market, banking and international affairs divisions.

The BOJ also decided on Monday to extend responsibilities of its executive director Shinichi Uchida, who has overseen international affairs, to include monetary policy.

The decision could affect the BOJ’s future monetary policy as whoever holds the post has sway in what tools the central bank uses in expanding stimulus, analysts say.

As a more junior-ranking BOJ official, Uchida played a key role in the bank’s decision in January 2016 to adopt negative interest rates – a move that proved hugely unpopular among the public and financial institutions.