The Bureau of Labor Statistics yesterday issued a major correction of employment data it had compiled for the Joint Economic Committee. Instead of the 8 million manufacturing jobs that the BLS said initally had been lost since 1979, the BLS said the correct figure is 2 million.

BLS officials said that a faulty computer run on state-by-state employment data led to the erroneous information which was supplied to the committee and which appeared in The Washington Post yesterday. The wrong information was not detected until yesterday morning when the Post story appeared, BLS officials said.

"I don't know how it could have gotten by" BLS personnel and into the hands of the JEC, said BLS commissioner Janet L. Norwood during a hearing of the committee yesterday. "I take responsibility for it. It won't happen again."

The corrected information shows that the states which lost the most jobs since 1979 were: Illinois, 324,000; Pennsylvania, 286,900; Ohio, 270,300; Michigan, 240,400; New York, 169,000, and Indiana, 128,800.

The number of jobs lost in the District should have been 800, with Maryland losing 30,000 and Virginia gaining 11,100 jobs. States with the highest job gains should have been California, 88,100; Florida, 79,700, and Arizona, 42,000.