The Nikkei stock index closed above the 18,000 threshold on Monday for the first time in more than 10 months as the continued weakening of the yen stoked hopes of improved profits abroad for Japanese exporters. 
The 225-issue Nikkei Stock Average ended up 138.61 points, or 0.77%, from Friday at 18,106.02, the highest since January 6, according to (Kyodo) news agency. 
The broader Topix index of all First Section issues on the Tokyo Stock Exchange finished 14.47 points, or 1.01%, higher at 1,442.93 and the JPX-Nikkei Index 400 rose to 12,945.20.