In September 2007, two members of the Boston Audio Society and the Audio Engineering Society published their study in which about half of the 554 double-blind ABX test listening trials made by 60 respondents showed the correct identification of high-resolution or CD-standard sampling rate. The results were no better than flipping a coin, producing 274 correct identifications (49.5% success), and it would have required at least 301 correct identifications given 554 trials (a modest 54.3% success rate) to exceed a 95% statistical confidence of audible difference, which will happen about once in twenty such tests by chance alone.[1]