By 1900, wealthy nations were faring much better, but the global average of life expectancy was still around 32. By 2021, however, the global average life expectancy age had more than doubled to 71. But how did that happen? For starters, it's important to note that life expectancy already has been fairly high in wealthy countries for decades. In 1950, developed nations like the US and Canada and most of western Europe and Japan had all life expectancies above 60 years of age