It is one of the most worrisome economic statistics of a year that was full of them: In 2021, according to the Census Bureau, the U.S. population grew at the slowest rate in recorded history.

This poor performance was due to slowing immigration, low birth rates, and of course a high number of deaths from COVID-19. Total population grew by just 0.1%, or 392,665. Even measured in absolute terms, that increase is smaller than during the confluence of World War I and the Spanish flu pandemic.

Inflation and unemployment rates get a lot of attention, justifiably. But this macroeconomic news ought to be of at least equal concern. That’s because — in economies as well as careers — what’s important is not only the level of achievement but also the momentum. The goal is to have a series of ascending successes pushing you toward successively stronger positions.