Illegal music downloads remain a problem worldwide, particularly in potentially huge markets such as Russia, India, and China. Moore urged governments to follow the example of the international enforcement action against Megaupload founder Kim Dotcom, accused by American prosecutors of facilitating millions of illegal downloads. Dotcom, who is fighting an attempt to extradite him from New Zealand to the United States, denies the allegations.
The report hailed the action against Megaupload and sites like The Pirate Bay — which has been blocked by several European countries — but it estimated that 32 percent of all Internet users still regularly downloaded pirated music.
"What other industry has to cope with a third of its customers being able to get copies of its products from illegal services?" Moore said.
With growth uneven across various countries and piracy still a stubborn problem, it could take years for the industry to return to its previous health. If it ever does.
Mulligan said he believes some of the lost revenue may never be recovered, with many casual users who used to buy the odd CD turning to free services such as YouTube, television music channels, or Internet radio instead.
"This is a case of managed decline," he said, predicting "a sustainable but smaller market built around more engaged music fans."
The IFPI's report: http://www.ifpi.org/content/section_resources/dmr2013.html
Raphael Satter can be reached on: http://raphae.li/twitter