A BMW five series is on display at the headquarters of the German luxury carmaker in Munich May 11, 2011. BMW will hold the company's annual shareholder meeting in Munich on May 12 Reuters

The last six months have been BMW's most successful in company history, with each month surpassing the one before.

While BMW has long been the world's best selling luxury car manufacturer, the German car maker is not alone in its recent success. According to J.P. Morgan analyst Ranjit Unnithan, luxury car profit margins are at historical highs, cash flows have never been better and balance sheets are strong.

Audi surpassed Mercedes-Benz as the world's second-largest luxury car maker by sales volume - sales were up 18% in the first half of the year. Mercedes-Benz was up 9.7%; and the company continues to generate more revenue per car than its competitors.

The comeback of luxury car makers in recent quarters is fueled by booming demand in China and a recovery in the U.S. according to a Marketwatch article.

In a statement Thursday, BMW sales chief Ian Robertson advised caution in expecting the sales boom to continue for much longer. Due to the model cycle and the year-on-year base effect, we do anticipate a somewhat slower rate of growth in the second half of the year.

[Source: Marketwatch]