Battling reduced travel spending and rising vehicle costs, Dollar Thrifty managed to trim its balance sheet from $2.6 billion at the end of February 2008 to $1.88 billion last month. That follows Dollar Thrifty successfully amending its senior secured credit facility and fleet financing agreements last month while establishing a secondary supplier agreement with Ford. In trading on the New York Stock Exchange, DTG shares rose 14 cents Monday to close at $1.07. At 655,683, its trading volume was three times its daily average.