By the end of 2011, three digital singles were issued eventually.
Sales of digital singles jumped 65 percent last year, to about 582 million units.
More digital singles were sold than CDs for the first time.
In 6 years of activities they have sold more than 18 million records (mostly digital singles).
Sales of digital singles first reached the million-units-a-week mark in November 2003.
Before the album, three digital singles were released over eight months.
There are certainly more factors involved in this than just the sale of digital singles.
I wonder if they considered the potential lost sales in the form of digital singles.
Both songs have also been released as digital singles.
She has sold more than 30.4 million digital singles as of January 2012.