Lexus sales increased a little more than 31% in May 2010 over May 2009’s total, easily enough forward movement to stay ahead of Mercedes-Benz and BMW. Cadillac was the luxury brand with the greatest percentage increase over May 2009, adding 4355 sales, a 54.3% jump. Jaguar, which just started selling the 2011 XJ at the very end of the month, posted a decline in sales measuring 17.6%. Among luxury auto brands, only the barely-breathing Saab suffered a greater percentage decrease in U.S. sales in May. Volvo, Lincoln, Porsche, and BMW all sold fewer vehicles this May than in the same period of last year.

So how does Lexus hold so firmly onto the #1 position in U.S. luxury auto sales? It certainly doesn’t happen this way in other markets, not even in Canada. Americans clearly love the isolated feel of a Lexus – serenity now – and hold fast to the reputation Lexus has built on quality. Check out all the totals in the Graph below to see just how far ahead Lexus really is.