The Nikkei closed at a new four-and-a-half year high at the end of trading yesterday (March 14th).
It was up by 1.5 per cent on the start of the day, a rise of 2.3 per cent since the beginning of the week, indicating a strong period of growth for the index.
Yoshiyuki Kondo, an analyst at Daiwa Securities, told Reuters that Haruhiko Kuroda being named as the Bank of Japan's next governor could be a boost to the market.
Kikuo Iwata and Hiroshi Nakaso have also been confirmed as the deputy governors of the bank and Mr Kondo said: "Approval by the upper house will boost hopes for more decisive and swift policy easing."
The Nikkei advanced 1.5 per cent to 12,560.95, which is the highest level since early September 2008. It has risen for four weeks in a row.
After losses were recorded on the index on Monday, Hirokazu Fujiki, strategist at Okasan Securities, suggested it was because some investors had decided to cash in on their profits.
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