According to a new study by AARP, the 50-plus population contributes so much to the economy, that if they were counted as their own country, they would make up the world’s third largest economy.

The Longevity Economy Outlook report found that Americans 50 and older contributed more than $8 trillion last year, which is equivalent to 40% of the U.S. economy’s entire GDP.

It also found that figure could grow to $28 trillion in the coming decades as Millennials and Generation Z turn 50 in 2031 and 2047, respectively.

Another key finding from the report is that caregivers make up a $604 billion “invisible workforce” by providing unpaid work, such as volunteering or caring for a grandchild or aging parent.

The report also noted that the market needs to catch up to the needs of this group by investing in more innovative solutions, creating flexible workplace options and continuing education opportunities.