The US four-week moving average of initial claims for unemployment insurance fell to 253,500 last week, down 6,500 from the previous week’s average, according to seasonally adjusted numbers released today by the US Department of Labor. The previous week’s average was revised upward by 250.

The four-week moving average decreases the volatility of the weekly numbers. Total initial claims for unemployment insurance for the week ended Nov. 12 were 235,000, down 19,000 from the previous week’s unrevised level. This is the lowest level for initial claims since Nov. 24, 1973, when it was 233,000.

This marks 89 consecutive weeks of initial claims below 300,000, the longest streak since 1970.

No special factors affected this week’s initial claims.

Bloomberg reports the biggest drop in initial claims since June suggests employers are loath to fire workers as the economy continues its modest expansion and the number of experienced applicants available for hiring remains limited. The decline contradicted the median estimate in a Bloomberg survey, which called for initial claims to increase to 257,000. “We’re exhausting the pool of workers that we can draw from out of the unemployed,” said Patrick Newport, an economist at IHS Global Insight in Lexington, Mass. “We’re approaching full employment, so we’re seeing really strong job gains, but they can’t continue for very long.”