Japan's Nikkei Stock Average climbed in the morning trade as Bank of Japan announced monetary stimulus but retreated and slumped at the end of session on investor concerns about further easing amid Spain downgrade. Nikkei 225 index dropped 0.43% or 40.94 points to 9,520.89. Advantest Corp rallied 8% on news it managed to end the quarter with profit, despite reporting fiscal-year loss. Kyocera jumped 4%. Although the firm reported a 3% fall in profit, it improved its outlook.