The legendary bond investor, known for his colorful writing, drew some interesting analogies in his latest market commentary. The Janus Capital investment manager’s January outlook is titled “It’s a Xanax World” and it kicks off with a comparison between Roman citizens being gifted “a day at the Coliseum” and the current wide array of modern distractions—sports, cellphone game apps, sexting, and fast food—as examples of opiates for the masses. “It’s a Xanax society,” he writes. “We love it.”

The point that Gross (eventually) gets around to is that the world’s many distractions make it easy to forget “that half of the U.S. population doesn’t go to work in the morning and that their real wages after conservatively calculated inflation have barely budged since the mid-1980’s.” (According to the Bureau of Labor Statistics, 59% of the U.S. population was employed in November, which is near a three decade low.)

Gross warns of a “demographic countdown.” The problem, as Gross sees it, is that there will be too few millennial workers to produce all the things that the aging baby boomer generation will want to consume. With that disparity on the horizon, he writes, developed nations like the U.S. would be wise to increase investments in developing markets with demographics more favorable to economic growth, and where the world’s goods will have to be made.

“Demographics may not rule absolutely, but they likely will dominate investment markets and returns for the next few decades until the Boomer phenomena fades away,” Gross writes.