The number of Americans filing new claims for unemployment benefits fell slightly more than expected last week, pointing to a sustained improvement in labor market conditions. Initial claims for state unemployment benefits declined 14,000 to a seasonally adjusted 298,000 for the week ended Aug. 16, the Labor Department said on Thursday. A Labor Department analyst said there were no special factors influencing the state level data. The four-week average of claims, considered a better measure of labor market trends as it irons out week-to-week volatility, rose 4,750 to 300,750.