Nikkei 225 falls sharply
Over 600 yen at one point due to low oil prices
A pedestrian passes an electronic board displaying the closing price of Nikkei stock average outside a brokerage in Tokyo, Japan on Monday, December 14, 2015. The 225-issue Nikkei index ended down 347.06 points, or 1.80 percent, to 18,883.42, a six-week closing low. (Photo by AFLO)