Source: The Washington Post - Link
The other policy in the toolkit is immigration.
If the United States wants more working-age people to contribute to our economy, there are millions of strivers around the world ready and eager to pitch in. Indeed, immigrants and their children have been a key driver of population, economic and productivity growth in the not-so-distant past, but dwindling immigration is another reason population growth slowed so much in the 2010s.
Immigration is key to a healthy economy over the long term as the birth rate continues to decline.