U.S. retail sales increased 0.5% in April, but most of the increased spending was at the gas pump, the Commerce Department said Thursday. Gasoline sales surged 4.6% in April as the price rose toward $3 a gallon. Excluding gasoline sales, seasonally adjusted retail sales rose 0.1% in April. The figures are not adjusted for inflation. Auto sales fell 0.4% in April. Excluding autos, retail sales increased 0.7%. Economists were expecting a larger increase of about 0.7% for overall sales and 0.8% excluding autos, according to a survey conducted by MarketWatch. In the past year, sales are up 6.6%. Real retail sales began the second quarter on a weak note, in line with forecasts that the economy would slow somewhat from the torrid 4.8% pace seen in the first quarter.