Despite the longest growth run in nearly three decades, Japan's economic outlook remains far from robust as uncertainty abounds over wage growth and business investment.

Under Abenomics, Prime Minister Shinzo Abe's program of radical monetary easing, fiscal spending and vows of structural reforms, the economy grew at an annualized rate of 0.5 percent in the October-December period, marking the eighth straight quarter of expansion. It slowed from a revised 2.2 percent increase in the previous quarter and was below the potential growth rate of around 1.0 percent.

Many economists expect the economy to keep growing at a moderate pace this year, but the biggest wild card could be volatility in financial markets after the recent global stock market rout.