Sri Lanka’s January trade deficit rose 49.7 per cent to $965.5 million year-on-year, central bank data showed on Monday. Gross official reserves fell 2.5 per cent to $5.81 billion in January from $5.96 billion a month ago and were sufficient to finance 3.4 months of imports. The central bank heavily spent reserves to defend the rupee currency in the second half of 2011.   Sri Lanka suffered a record trade deficit of $9.7 billion last year, prompting the central bank to raise policy rates and allow flexibility in the exchange rate by not intervening in the market.