"As domestic demand is imploding, so is foreign demand," Weinberg added. "Exports are flat year-on-year. This is not to say that net exports are not rising. However, the flat gross exports mean industrial output to make goods for export is not growing."
"Without growth of either exports or domestic consumer spending, industrial production has stalled," Weinberg said.
On Tuesday, data showed German industrial new orders dropping by 7.4 percent on the month in January – the biggest monthly fall since 2009. According to Reuters, a breakdown of the January figures showed a drop of 10.5 percent in domestic demand and a contraction of 4.9 percent in foreign orders.
However, industrial production data released Wednesday gave some relief to analysts and investors. Industrial production rose by 2.8 percent on the month after contracting 2.4 percent in December.
Carsten Brzeski, chief economist at ING, said in an email on Wednesday that "the increase in industrial production shows that the shocking drop in December was mainly driven by the Christmas season and the cold winter weather. At the same time, however, the fact that on the year industrial production has remained flat shows just how difficult it is for the industry to get out of stagnation."
Looking at the hard data, Weinberg concluded: "Germany's real economic indicators are faltering. A clear crack in the trajectory is evident. Those are the facts. Invest accordingly."
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