WASHINGTON (Reuters) - The U.S. current account deficit was the smallest in four years in the third quarter as exports increased and more income was earned abroad, a government report showed on Tuesday. The Commerce Department said the current account gap, which measures the flow of goods, services and investments into and out of the country, narrowed to $94.8 billion. That was the smallest since the third quarter of 2009 and was an improvement from a revised shortfall of $96.6 billion in the second quarter. It represented 2.2 percent of gross domestic product, the smallest share since the first quarter of 1998. It was down from 2.3 percent in the July-September period. Economists polled by Reuters had forecast the current account deficit widening to $100 billion in the third quarter from a previously reported $98.9 billion in the prior period. The shortfall on the current account has shrunk from a peak of 6.2 percent of GDP in the fourth quarter of 2005, in part because of a significant increase in the volume of oil exports. In the third quarter, exports of goods and services increased 0.6 percent to $765.1 billion, while imports rose 0.4 percent. The surplus on income increased to $60.0 billion from $56.0 billion in the second quarter. Net unilateral transfers decreased to $34.1 billion from $34.5 billion. (Reporting by Lucia Mutikani; Editing by Andrea Ricci)