Tokyo: Japan's consumer prices fell 0.4 per cent in May from a year earlier due to declining energy prices, marking the biggest drop in over three years, the government said on Friday. The core consumer price index (CPI), which includes oil products but excludes volatile fresh food prices, stood at 103.0 against the 2010 base of 100, the Ministry of Internal Affairs and Communications said. The fall, following a 0.3 per cent drop the previous month, was largely prompted by continued decline in energy prices, which plunged 12.6 per cent from a year earlier, with gasoline prices dropping 16.1 per cent and electricity fees sliding 9.6 per cent, Xinhua news agency reported. It marked the biggest drop since April 2013 when the figure also slid 0.4 per cent, despite Japanese Prime Minister Shinzo Abe's efforts to push up the consumer prices. The core CPI for Tokyo's 23 wards in May, seen as indicator of nationwide prices, dropped 0.5 per cent from a year earlier to 101.6, declining for the sixth straight month. A separate report from the ministry showed that average monthly household spending in May also dropped for the third straight month by an inflation-adjusted 1.1 percent from a year earlier. With the Bank of Japan's goal of raising the inflation rate to 2 per cent further away, market speculation on additional monetary easing policy has been on the rise.