General Motors today said it would terminate its endorsement deal with Tiger Woods in December, ending the pro golfer's nine-year stint with the automaker.

GM issued a statement asserting that both GM and Woods "agreed to a mutual and amicable separation that included a desire for more personal time for the golfer who is expecting his second child in late winter as well as the search for budget efficiencies during a difficult economy for GM."

Tiger Woods signed with GM nine years ago, but has been used sparingly by the automaker. Earlier this year, however, GM began featuring Woods front and center to boost sales of the Buick Enclave luxury crossover. TV spots featured Woods discussing what he likes about his Enclave.

In June, GM launched a promotion for Buick called "Tee Off with Tiger," where fans were asked to guess Woods' score on each hole he played through the fall, for a chance to win his services as a caddy at Torrey Pines golf course.

As the auto industry continues to sputter and the big carmakers seek a federal bailout, it's little surprise that media spending in the category has begun to erode.

According to Nielsen Monitor-Plus data, Ford and Chrysler each spent 22 percent less on advertising in 2008, while General Motors' ad spend dropped 6 percent. Through July, GM retained its position as the top-spending auto company, investing $1.25 billion in advertising.