Real gross domestic product in the United States increased at an annual rate of 1.8% in the first quarter, based on the revised estimate released by the Commerce Department's Bureau of Economic Analysis Wednesday. GDP — a comprehensive measure of the output of goods and services in America — grew 3.1% in the fourth quarter, but lost speed in the first three months of 2011, as imports surged, exports fell, personal consumption declined and cuts were made in federal spending. Analysts with Econoday noted the government's GDP report indicated relative strength in personal spending and investment in inventory as well as investments made in business equipment and software. Write to Kerri Panchuk.