A year after Prince's death, expert calls him 'greatest performer of his generation'

— -- One year after his death, rock critic Alan Light has called Prince the "greatest performer of his generation."

Light, the author of "Let's Go Crazy: Prince and the Making of Purple Rain," told ABC News that fan of the future might not be able to see just how good he was.

"There is no easily, legally available document of Prince on stage in the glory years," he said. "If we're going to tell generations moving forward this was the greatest performer of his generation, this guy could do things on stage that nobody else could do, we need to be able to show that."

To that end, Light believes it's imperative that Prince's estate finds a way to ensure to illustrate the musician's impact. He claims younger audiences are not as aware of Prince's genius as they should be because Prince kept his music off streaming services and YouTube.

"I think that there's really a huge reintroduction that needs to happen, to generate an awareness for those who weren't around for the glory years to know what this guy was really about," Light added.

In addition to Light's comments, Billboard reports that Prince sold more albums in 2016 than any other artist.

Of those 7.7 million copies, 2.3 million were traditional album sales. Prince's best-selling songs last year include "Purple Rain," with 621,000 downloads, followed by "Little Red Corvette," "Let's Go Crazy" and "Kiss." His best-selling albums last year were The Very Best of Prince, with 668,000 copies sold, followed by Purple Rain and 1999.

Also of note: Prince's music has been played a lot more on the radio since his death, which has continued into this year, according to Billboard. His most popular hit on the radio this year is "When Doves Cry."

Prince died on April 21, 2016 at the age of 57 from an accidental overdose of fentanyl, which he "self-administered," the Midwest Medical Examiner's Office in Minnesota reported weeks after his death.