Japan's benchmark Nikkei 225 Stock Average soared 2.3 per cent Wednesday as market sentiment was bolstered by a weaker yen and gains on other Asian markets. The Nikkei gained 208.27 points to end at 9,260.34 while the broader Topix index was up 16.16 points, or 2.05 per cent, at 802.96, according to a report of DPA.