The US four-week moving average of initial claims for unemployment insurance fell to 235,250 last week, down 5,750 from the previous week’s average, according to seasonally adjusted numbers released today by the US Department of Labor. This is the lowest level for this average since April 14, 1973, when it was 232,750.

The previous week’s average was revised up by 250.

The four-week moving average decreases the volatility of the weekly numbers. Total initial claims for unemployment insurance for the week ended May 20 rose to 234,000, up 1,000 from the previous week’s level, which was revised upward by 1,000.

No special factors affected this week’s initial claims.

MarketWatch reports the number of Americans applying for and receiving unemployment benefits continues to drop to levels last seen nearly a half century ago, a sign the US labor market remains quite robust eight years into an economic expansion. The US economy has been churning out new jobs at a rapid pace since 2011, pulling the unemployment rate down to 4.4% and eliciting widespread complaints from businesses that they cannot find enough skilled workers to fill open positions.