20% of elderly Americans are either employed or looking for work. Here's why.

Miguel Angel Martinez Sarmiento works as a barista in a branch of the US coffee house 'Starbucks' and pours milk into a can. All the employees at the coffee shop, which opened in Del Valle Sur at the beginning of September, are over 60 years old. (Photo by Antonia Märzhäuser/picture alliance via Getty Images)