"The pay gap has accelerated as globalization opened up workforces and lower level jobs are increasingly automated and off-shored. This reduces the number of jobs available and increases competition for those left, keeping pay down," said Frost.
"In contrast, pay is going up for senior managers where skills such as emotional intelligence, creative thinking and advanced judgement are in high demand and short supply. In addition, senior managers are increasingly being asked to take on more responsibilities and more complex work."
Europe was the region where the greatest number of countries had experienced a decrease in the pay gap, with these including Switzerland, France and Poland.
"In response to the recession, many companies in Europe introduced communal pay cuts to avoid job losses," said Frost.
"In comparison, U.S. companies more frequently cut jobs and asked the remaining senior managers to expand their scope of work during the recession. Many of those who remained employed received a pay increase as compensation for their expanded role, leading in part to the widening job level pay gap."
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