GM’s Cadillac Records Biggest Year-to-Date Gain Since Disco Era

General Motors Co.’s Cadillac brand posted its biggest gain so far this year since Gerald Ford was president, the U.S. celebrated its 200th birthday and “The Hustle” won a Grammy.

Through May, Cadillac sales increased 38 percent to 69,750. That was the brand’s biggest year-to-date increase since 1976, when sales jumped 45 percent to 135,258 and Van McCoy’s “The Hustle” won for best pop instrumental performance.