BERLIN, Sept. 15 (Xinhua) -- German stocks were up slightly at the start of trading on Tuesday, with the benchmark DAX index increasing 27.15 points, or 0.21 percent, opening at 13,220.81 points.

The biggest winner among Germany's 30 largest listed companies at the start of trading was building materials company HeidelbergCement, increasing by 1.17 percent, followed by chemical giant Bayer with 0.94 percent and car manufacturer Volkswagen with 0.75 percent.

Shares of Munich Re fell by 0.57 percent. The German reinsurer was the biggest loser at the start of trading on Tuesday.

The number of people employed in German manufacturing in July decreased by 2.9 percent year-on-year, the Federal Statistical Office announced on Tuesday.

On Tuesday, the German Leibniz Centre for European Economic Research is scheduled to publish its economic expectations for Germany. In August, its monthly indicator for economic sentiment increased significantly by 12.2 points to 71.5 points.

The yield on German ten-year bonds went down 0.003 percentage points to minus 0.479 percent, and the euro was trading at 1.1867 U.S. dollars, decreasing slightly by 0.01 percent on Tuesday morning.