The total number of digital singles sold in the UK has passed one billion, according to the Official Charts Company.
The landmark figure was reached on Monday evening (April 9), nine years after legal downloads launched in the UK.
Adele's Someone Like You has also been confirmed as the most downloaded track, with 1.46 million sales.
Moves Like Jagger, by Maroon 5 and Christina Aguilera, is in second place (1.4 million), while Gotye's Somebody That I Used To Know is in third (1.38 million).
I Gotta Feeling by Black Eyes Peas and Rihanna's We Found Love are fourth and fifth.
In all, 16 tracks have passed one million downloads on the UK chart and total sales continue to climb steadily.
Around 3.7 million singles are now sold each week - but when official downloads began in 2004 just 3.77 million downloads were recorded during the entire year.
The BPI, the British record industry's trade association, said it expected new technology to boost sales even further.
"As fans increasingly download music on the move, tablets, smartphones and connected cars will drive another phase in digital music’s expansion," said BPI Chief Executive Geoff Taylor.
The figures represent individual tracks rather than full album downloads or streaming services like Spotify.