The analysis by The Bill & Melinda Gates Foundation and The Clinton Foundation found that although progress for women had been made in some areas, "critical barriers" remained.
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"Women's participation in the labor force has stagnated for two decades—and they still earn less than men," the report said, and highlighted that women remained under-represented in leadership positions across the world.
In the U.K., Altmann found that older women face a number of hurdles when it comes to work, such as the frequent need to combine work and caring for ageing parents. Many are also disadvantaged in state and private pensions, she argued, as a result of lower wages than men, and of having taken time out to have children earlier in their careers.
But the report found that older women could make a major contribution to the economy. If 600,000 more older women worked part-time, some £9 billion could be added to U.K. gross domestic product (GDP) each year, the report found, and this amount rises to £20 billion if these women worked full-time.
"The potential economic gain from having more older women in the workplace is significant," Altmann added.