Again, it is the efficiency argument which is the basis for the differential, even zero, taxation of capital gains and other income from capital.

FORBES: Taxing Capital Isn't About Fair: It's About Efficiency

German efficiency and once-matchless engineering can reduce that differential and justify higher prices, but only to a degree.

ECONOMIST: Germany's economy

The cost differential is driven by air pollution, interconnection and the economics of fuel efficiency.

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