Costco’s power in the auto industry is growing.

On Saturday, the budget retailer announced it is once again partnering with General Motors for its popular Holiday Sales Event, which will last from October 1 to January 3.

Last year, 58,000 vehicles were sold during the promotion, a 34% increase over 2014 sales during the promotion. More than half of the people who purchased vehicles through the event said they switched to a General Motors brand such as Chevrolet, Buick, or Cadillac because of the promotion. MORE