Alex Davies / Business Insider
The 2014 Cadillac CTS at the New York Auto Show.
Over the past two years, Cadillac has done an excellent job with new or heavily renovated versions of its ATS, XTS, and CTS sedans, and now it's reaping the rewards.
Cadillac sold 13,808 cars in the US in May, a 39.9% increase over its May 2012 numbers, General Motors announced this morning.
That's the fastest the brand has grown in nearly 40 years — since "the days of disco," as a GM exec put it on a press call.
This past month is not an outlier. Cadillac year-to-date U.S. sales are up 37.6% over 2012. According to GM, the last time the brand posted that big an increase was in 1976.
US vice president of Cadillac sales Chase Hawkins said the numbers are in part thanks to "particular growth in some of our key markets, like New York and California."
The brand also has big plans for China — now the world's largest auto market — where it wants to triple sales by 2015.
GM's overall U.S. sales are up 3.1% this month, unimpressive compared to Chrysler (up 11%) and Ford (up 14%). GM said the difference can be accounted for by the timing of customer deliveries.
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