Japan’s benchmark Nikkei 225 index is set to climb further next year, despite already rising more than 70 percent over the past two years, analysts say.

“Corporate earnings will be stronger, and drive up the Nikkei to 22,500 by September,” said Eiji Kinouchi, Daiwa Securities’ chief technical analyst and one of Tokyo’s leading bulls. He is forecasting the Nikkei will end the year at 22,000. Daiwa forecasts the U.S. dollar will fetch around 124-134 yen in the autumn, but the pair will likely slip back to around current levels of 120 yen by the end of 2015.

Earnings growth for major Japanese companies will likely be in the double digits and help to bolster Japan’s shares, according to a Jefferies note. That, the brokerage’s analysts believe, will lift the Nikkei to 19,500 even if the yen stabilizes at the current 120 yen level against the dollar. Jefferies is forecasting the U.S. dollar will strengthen to 124 yen in a year’s time.

Headwinds lurking ahead

Some are a little more cautious. “The dollar-yen moved a lot in 2014 and there are some headwind risks lurking ahead next year, such as the Greek elections, the Russian ruble crisis and volatile oil prices,” said Kengo Suzuki, Mizuho Securities’ chief currency strategist.

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Suzuki is forecasting the yen will strengthen, with the U.S. dollar trading at just 113-115 yen in the first months of 2015; if the widely expected U.S. rate hike takes place the over the summer, he reckons that will spur a return to more dollar buying. Assuming the rate hike takes place, Suzuki sees the pair at 128-138 by the end of the year.