Music sales grew at the fastest rate in almost two decades last year as digital subscriptions outstripped physical revenues for the first time.

Total recorded music revenue advanced 3.2% to $15bn (£10.5bn) in 2015, driven by soaring subscriptions to streaming services like Spotify, Apple Music, Amazon Prime and Deezer.

The International Federation of the Phonographic Industry (IFPI) said such digital sources accounted for 45% of total revenues last year, compared to 39% from physical sales.

The boom in subscriptions drove the fastest overall growth in recorded music sales since 1998, when revenues jumped 4.8% year on year.

But the IFPI said there was a “fundamental weakness underlying this recovery” because consumers were paying less to stream music than they were to purchase albums.

“Music is being consumed at record levels, but this explosion in consumption is not returning a fair remuneration to artists and record labels,” the IFPI said.

The body’s boss, Frances Moore, added that the music market was distorted by a “value gap.”

He said: “The message is clear and it comes from a united music community: the value gap is the biggest constraint to revenue growth.

“Change is needed – and it is to policy makers that the music sector looks to effect change.”