Philippine imports grew at their slowest rate in one and a half years in May, largely due to a steep decline in oil and cereal purchases, the government said Tuesday. Total imports for the month rose 1.6 percent to $4.89 billion compared to a year earlier, the National Statistics Office said in a statement. It was their slowest year-on-year advance since imports started rising in November 2009 from the slump caused by the global economic crisis, according to National Statistics Office data. May imports were also down 11.1 percent from the previous month. Analyst Alvin Arogo of DBP-Daiwa Securities said the weak figures did not necessarily augur well for the Philippine trade balance. \"There\'s a possibility the trade deficit will worsen. I don\'t expect a significant improvement (in exports), meaning the deficit won\'t probably shrink,\" Arogo told Dow Jones Newswires. Raw materials and intermediate goods, which are processed or assembled in the Philippines to be sold abroad, accounted for 47.3 percent of all May imports, according to the government data. Imports of oil products, the second-largest group, plunged 33.5 percent to $686 million. Cereal product imports dropped 18.8 percent to $190 million, while transport equipment imports slipped 10.8 percent to $217 million. Meanwhile, manufacturing output, adjusted for inflation, grew just 0.9 percent in May from a year earlier, the government agency said. Despite the weak data in May, total imports for the five months to May grew 17.4 percent to about $26 billion, and the trade deficit jumped 80.81 percent to $5.37 billion after exports rose 7.5 percent to $20.63 billion, the government said.