Retirement systems around the world are expected to face a significant burden in the next 50 years.

The number of people over the age of 60 is expected to double from 841 million in 2013, to over 2 billion by 2050, according to the UN. What’s more this has been accompanied by falling global birth rates.

In fact, the global share of people over the age of 60 has gone from 9.2% in 1990, to 11.7% in 2013 and is expected to hit 21.1% in 2050, according to Bank of America’s Sarbjit Nahal and Beijia Ma. The number of people over the age of 60 (older persons) is set to exceed the number of children for the first time, by 2047.

“Longevity risk is hugely underestimated,” the write. “Longevity risk will be one of the most significant challenges facing retirement systems over the next 50Y, with global annuity and pension-related exposure estimated to be as high as US$15-25tn.”

Nahal and Ma do however see a silver lining to longevity, namely, that the spending power of those over 60 is expected to hit $US15 trillion by 2020. In the U.S. and Japan, the longevity sector is expected to account for over 50% of GDP by 2030.

This chart from Nahal and Ma shows the percentage of the global population over the age of 65 is going to increase significantly by 2050.

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