Possible causes and effects of slow wage growth

There's some evidence that inequality may be rising, and in most places the recession that followed the financial crisis had dire effects on wages. According to the Economist, despite five years of growth American real wages are still 1.2% below what they were at the beginning of 2009. In Britain, real wages fell every year between 2009 and 2014, the longest decline since the mid-1800s. In 2014 median pay was 10% below its 2008 high. Why is this?

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