Dance Club Songs chart in 2004. Discovery had sold at least 2.6 million copies as of 2005. Critical reception Discovery received generally positive reviews from critics. At Metacritic, which assigns a normalized rating out of 100 to reviews from mainstream publications, the album received an average score of 74, based on 19 reviews. AllMusic's John Bush said that, with their comprehensive productions and loops of manifold elements, Daft Punk had developed a sound that was "worthy of bygone electro-pop technicians from Giorgio Moroder to Todd Rundgren to Steve Miller." Q wrote that the album was vigorous and innovative in its exploration of "old questions and spent ideals", hailing it as "a towering, persuasive tour de force" that "transcends the dance label" with no shortage of ideas, humor, or "brilliance". Q named Discovery one of the best 50 albums of 2001. Joshua Clover, writing in Spin, dubbed Discovery disco's "latest triumph" and said although it "flags a bit" before the end, the opening stretch of songs was on-par with albums such as Prince's Sign o' the Times (1987) and Nirvana's Nevermind (1991). Stephen Dalton from NME found the record's pop art ideas enthralling and credited Daft Punk for "re-inventing the mid-'80s as the coolest pop era ever". In Entertainment Weekly, Will Hermes wrote that the "beat editing and EQ wizardry" still excite after Homework, despite the newly imbued sense of humor. Mixmag called it "the perfect non-pop pop album" and said Daft Punk had "altered the course of dance music for the second time". Ben Ratliff from Rolling Stone was less impressed and wrote that few songs on Discovery matched the grandiosity of "One More Time". He found most of them "muddled – not only in the spectrum between serious and jokey but in its sense of an identity." In The Guardian, Alexis Petridis felt Daft Punk's attempt to "salvage" older musical references resembled Homework, but was less coherent and successful. Pitchfork critic Ryan Schreiber found the "prog and disco" hybrid "relatively harmless" and said that it was not "meant to be judged on its lyrics", which he dismissed as amateurish and commonplace. Robert Christgau, writing in The Village Voice, facetiously said the album may appeal to young enthusiasts of Berlin techno and computing, but it was too "French" and "" for American tastes. In a retrospective review for The Rolling Stone Album Guide (2004), Douglas Wolk gave Discovery three and