The Nikkei has reached a new five-year high this week and analysts believe the strong performance in recent weeks is going to continue for the rest of the year.
Specialists expect the Nikkei to be up 40 per cent by the end of 2013 and the index has already grown 30 per cent in the last three months.
Kyoya Okazawa, head of global equities and commodity derivatives at BNP Paribas in Tokyo, told Reuters that the Bank of Japan's (BoJ's) monetary policy has had a major impact on investors.
He explained the changes announced by the BoJ has changed where the Japanese market is heading in the future, so "we should reset our targets in order to maintain our bullish stance on the Japanese stocks".
However, the analysts are now predicting that the yen is going to drop 18 per cent against the dollar by the end of the year, indicating not everything will go well for the Japanese economy in 2013.
At the midday break, the Nikkei was up by 0.8 per cent to stand at 13,398.41 and had reached as high as 13,496.28, the index's highest since July 2008, during the morning session.
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