Monster Worldwide, which issues a detailed monthly report of online job ads, said the overall Monster Employment Index grew 2 points to 159.

The report found "accelerated" recruitment in mining, but a continued decline in online ads for manufacturing and construction jobs.

Education, healthcare, accommodation and food service, and finance and insurance all showed growth during the month, the report said.

By regions, online job listings in the Pacific region held steady, while the East South region shrank slightly. All other regions -- the West North Central, New England, West South Central, Middle Atlantic, East North Central, South Atlantic and Mountain regions -- showed modest growth, the report said.