Even as physical sales of music have drastically declined in the digital and streaming era, people are still buying Pink Floyd's The Dark Side of the Moon. Decades after it ended its historic chart run, it sells a couple of hundred copies every day and the 2017 solar eclipse caused a spike in sales.

Billboard says that it sold more than 1,000 copies on Aug. 21, 2017, the day of the eclipse, an increase of more than 160 percent. It was enough to put Dark Side atop iTunes' albums chart for the day, and, coupled with streaming figures, put it at No. 173 on the Billboard 200.

Pink Floyd have certainly earned quite a comfortable living simply off royalties from 1973's Dark Side, but drummer Nick Mason insists the band's take hasn't been as massive as one would imagine. “We weren’t some huge big band before The Dark Side of the Moon," he tells the Irish Times. "And because we knew Dark Side was never the sort of album you would get recorded in a month, we renegotiated our contract with the label so that we would get more studio time, but at the cost of a lower royalty rate on the album’s sales.”

So Floyd sacrificed long-term profits, but Dark Side got made – it took almost a year – and went on to become one of the top-selling albums ever. Mason insists that these days, no other group would be allowed that kinda of time to find themselves in the studio -- or put out something as groundbreaking as the record Floyd came up with.

“It was so different, so strange-sounding,” he says. “Pink Floyd were always the outsiders, we were never a Beatles/Stones-type band because we were viewed as being a psychedelic band. And no band today would be allowed to more or less live in a studio for a year just for one album.”

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