There’s something odd going on in the music industry.

While physical CD sales are decreasing year after year, due to online music piracy, digital sales are booming.

Today the BPI reports that since the launch of the first legal store in 2004, UK music fans have spent more than £1 billion on digital music.

“British music fans enjoy the world’s most competitive and innovative digital music scene, propelling all-time sales of digital singles and albums past the £1bn mark,” BPI Chief Executive Geoff Taylor said.

“The strength of British music means there is fantastic potential for further growth.”

“Adele’s 21, the biggest seller of 2011, is already the UK’s biggest-selling digital album of all time. The hard work done by UK record labels in pushing forward the digital music market is paying off for consumers, digital retailers and the music community,” Taylor added.

According to the BPI 19.5% of the population made at least one digital music purchase in 2010, a figure that continues to go up every year.