With Americans living longer and spending more years in retirement, the nation's changing demographics are "putting the U.S. retirement system under immense strain," according to BlackRock CEO Larry Fink in his annual shareholder letter. 

One way to fix it, he suggests, is for Americans to work longer before they head into retirement.

"No one should have to work longer than they want to. But I do think it's a bit crazy that our anchor idea for the right retirement age — 65 years old — originates from the time of the Ottoman Empire," Fink wrote in his 2024 letter, which largely focuses on the retirement crisis facing the U.S. and other nations as their populations age. 

Fink, who is worth an estimated $1.2 billion, notes that many 65-year-olds in the early 1950s didn't get a chance to retire because many had already passed away. In other words, he writes, more than half of workers who had paid into Social Security never got a penny because they died before they could claim the benefit.