HANOI :The World Bank on Monday trimmed its forecast for Vietnam's economic growth on evidence that U.S. tariffs were starting to have an impact on the Southeast Asian exporter's shipments. The World Bank cut its GDP forecast for Vietnam to 6.6 per cent from 6.8 per cent this year, saying activity is expected to moderate over the rest of the year as export growth normalises after a strong first-half performance. The World Bank's new forecast is significantly lower than the government's official