South Korea recorded a record trade surplus of $3.93 billion in April mainly because slashed spending and investment slowed imports, the ministry of commerce, industry and energy said yesterday. The record surplus compares to a $1.41 billion deficit a year ago. This is the sixth consecutive monthly surplus since November 1997. FOB exports in April rose a mere 7 per cent from a year ago, while imports on a CIF basis plunged 35.5 per cent. Economists said the structure of the surplus was a worry because already weak export growth would crumble unless the country could import necessary raw materials.