ECONOMIC GROWTH SEEN SLUGGISH IN BENELUX COUNTRIES Economic growth will remain sluggish in the Netherlands and Belgium next year and unemployment may rise, the Organisation for Economic Cooperation and Development forecast. Belgium's GDP growth may slow down to 1.5 pct this year and next year, bringing a rise in the number of jobless, the OECD said in its semi-annual survey. Belgian inflation could stabilise at 1.5 to 2.0 pct, while the current account surplus will probably remain large at about three pct of GDP. While the Belgian government has made progress in trimming its borrowing requirement, "it will probably be insufficient to check the self-sustaining nature of the deficit," the OECD said. In the Netherlands real GDP growth will also slip to 1.5 pct this year and one pct in 1988, with Dutch exports becoming less competitive and imports rising. "Employment is forecast to decelerate as well, reflecting more sluggish growth in the private sector and budgetary cuts," the report said. Dutch consumer prices are set to fall by 0.5 pct in 1987 and stay stable in 1988, partly as a result of declining domestic gas prices. Luxembourg's economy, by contrast, will see slightly faster growth in GDP this year as a result of an upward movement in wages. But real growth in consumption will ease next year.