CHICAGO (MarketWatch) -- Union membership among U.S. workers dipped slightly to 11.8% last year from 11.9% in 2010, the Bureau of Labor Statistics said Friday. There were about 14.8 million unionized wage and salaried workers in the country last year, down from 17.7 million in 1983, when the data were first compiled and union membership stood at 20%. In the public sector, the union membership rate stood at 37%, compared to 6.9% in the private sector. And full-time wage and salary workers belonging to a union had median usual weekly earnings of $938 last year, compared with the $729 brought in by non-unionized ones.

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BOSTON (MarketWatch) -- Infinity Pharmaceuticals shares plunged nearly 40% to $6.05 after the biotech group reported disappointing data from a Phase II clinical trial for its drug saridegib, or IPI-926, in the treatment of advanced pancreatic cancer. Infinity tested the drug in combination with gemcitabine, a leading treatment for the disease. The company said that preliminary results showed that patients taking a placebo with gemcitabine lived slightly longer than those who took saridegib and gemcitabine. As a result, Infinity is halting the study. The company said it is still proceeding with Phase II trials with the drug in the treatment the cancers myelofibrosis and chondrosarcoma.

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