The number of Americans filing for unemployment benefits unexpectedly fell last week, pointing to a tightening labor market and strengthening economy at the start of the year.

Initial claims for state unemployment benefits slipped 1,000 to a seasonally adjusted 230,000 for the week ended Jan. 27, the Labor Department said on Thursday. Data for the prior week was revised to show 2,000 fewer claims received than previously reported.

Economists polled by Reuters had forecast claims rising to 238,000 in the latest week. The Labor Department said claims for Maine were estimated last week. It also said claims-taking procedures in Puerto Rico and the Virgin Islands had still not returned to normal months after the territories were slammed by Hurricanes Irma and Maria.

Last week marked the 152nd straight week that claims remained below the 300,000 threshold, which is associated with a strong labor market. That is the longest such stretch since 1970, when the labor market was much smaller.