Public opinion measurement was subcontracted to the National Opinion Research Center (NORC) of the University of Chicago, and their report was released beginning in February, 1965. The FAA was displeased by the overly academic style of the report, but stressed the positive findings, saying "the overwhelming majority felt they could learn to live with the numbers and kinds of booms experienced." Indeed, the NORC reported that 73% of subjects in the study said that they could live indefinitely with eight sonic booms per day, while 25% said that they couldn't. About 3% of the population telephoned, sued, or wrote protest letters, but Oklahoma City surgeons and hospitals filed no complaints.