International Enterprise Singapore (IE Singapore), the country's trade agency, released disappointing November trade data on Monday.
Non-oil domestic exports dropped 0.3 percent on-month and 2.5 percent on-year. Economists polled by Reuters had expected exports to rise 1.9 percent year-on-year and 3.5 percent month-on-month after seasonal adjustments.
Electronics exports fell 16.5 percent year-on-year in November while pharmaceutical shipments rose 29.6 percent, IE Singapore said. It also said exports of ship and boat structures, a category that includes oil rigs, rose 109.6 percent from a year earlier.
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Non-oil domestic exports totaled S$14.24 billion ($11.67 billion) in November, down from S$15.17 billion in October.
Domestic exports of electronic products fell to S$4.70 billion in November from S$4.98 billion in October but IE Singapore said they rose month-on-month after seasonal adjustments.
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Non-oil domestic exports to the European Union, Singapore's largest market, edged up 0.5 percent in November from a year earlier, after an 8.9 percent increase in October.
IE Singapore predicts non-oil domestic exports will grow by 2-4 percent in 2013, after lowering the 2012 growth outlook to 2-3 percent from 4-5 percent.
Singapore last month cut its 2012 economic growth outlook to "around 1.5 percent" from an earlier 1.5 to 2.5 percent.
Singapore's monthly exports tend to be unpredictable because a significant portion involves inputs for pharmaceuticals and oil rigs, which can vary sharply from month to month.