General Motors Corp. is reporting the largest annual loss ever for a U.S. automotive company. GM said Tuesday it lost $38.7 billion in 2007. The loss largely was due to a third-quarter charge related to unused tax credits. The loss topped the previous record GM set in 1992, when it lost $23.4 billion. That's according to Standard & Poor's Compustat. Separately, GM is offering a new round of buyouts to 74,000 U.S. hourly workers.