WASHINGTON — The fewest people in nearly 50 years sought unemployment benefits last week, a sign of a strong job market and an unusually low level of layoffs.

Yet the decline in applications for jobless aid isn’t due solely to a tight employment picture. Many states have imposed stricter rules on their unemployment insurance programs – from making it harder to qualify to reducing the duration of benefits to cutting payouts.

The combined effect has been to reduce the number of unemployed people who apply for and receive aid, economists say. Nationwide, just 30 percent of people out of work now receive unemployment insurance, down from about 40 percent before the Great Recession.

The historically low level of people seeking aid “tells us we have a strong labor market, and that we’ve made policy changes that mean fewer people can qualify for benefits,” said Martha Gimbel, research director at job listings website Indeed.

Weekly applications for unemployment benefits dropped 8,000 to a seasonally adjusted 196,000 last week, the Labor Department said Thursday. That is the lowest level since 1969. The four-week average, a less volatile measure, fell to 207,000, also the lowest point in 50 years.

The decline is all the more remarkable once you take into account population growth. The size of America’s workforce has doubled since the late 1960s to 162 million.

Still, dwindling unemployment claims send a signal of strength about the job market and the economy. Applications for jobless aid typically track layoffs. So the continuing decline – applications have tumbled for four straight weeks – shows that most businesses are confident enough about future customer demand to keep their staffs intact.

That confidence is spurring more hiring, too: Job growth rebounded last month after a sharp slowdown in February, suggesting that the economy remains resilient in its 10th year of expansion.

Early this year, many analysts were concerned that growth was stalling, with the global economy weakening, the Trump administration and China locked in a trade war, and consumers reining in their spending, as the benefits of the Trump administration’s tax cut have faded. Most Americans got a financial boost last year from the tax cut, but it was a one-time bump.

But falling applications for jobless aid indicate that employers don’t foresee an economic slowdown anytime soon.

Another reason for the decline is that long-term unemployment remains much higher than in previous periods when the unemployment rate fell as low as last month’s figure of 3.8 percent. People who have been out of work for 27 weeks or more aren’t eligible for unemployment insurance.