BERLIN — German automaker BMW AG says its third-quarter earnings were 1.8 percent lower than a year earlier as a result of increased costs for investments, research and development.

The luxury car maker said Tuesday that it earned 1.79 billion euros ($2.08 billion) in the July-September period, down from 1.82 billion euros last year. Revenue edged up 0.3 percent to 23.42 billion euros from 23.36 billion euros.

The company said the BMW Group, which also includes Mini and Rolls-Royce, delivered 590,415 vehicles in the third quarter, 1.2 percent more than a year earlier. Its core brand was helped by the new 5 Series, launched in February.

BMW said it is forecasting a “solid” increase in pre-tax profit for the full year, having previously predicted a “slight” rise.