For the third consecutive month, Tokyo's cost of living has risen with quiet insistence, as August's consumer price index climbed to 1.8 percent year-over-year even as the government worked to soften the blow of energy costs. In a nation where deflation haunted the economy for decades, this sustained upward drift carries a weight beyond its modest numerical size. The Bank of Japan, which has only recently begun loosening its grip on ultra-low interest rates, now faces a data landscape that makes the case for further tightening increasingly difficult to set aside.