The number of Americans filing for unemployment benefits dropped to the lowest level in nearly half a century.

The Labor Department says claims for jobless aid fell by 5,000 last week to 192,000, lowest since September 1969. The four-week average, which is less volatile, dropped by 6,000 to 201,250, lowest since November 1969.

Weekly claims have been at historically low levels — below 300,000 — for more than four years.

Unemployment claims are a proxy for layoffs. The low levels show that most American workers enjoy job security. The employment rate is 3.8%, the lowest in almost 50 years.