As reported by Billboard, CD sales in the United States increased year-over-year for the first time since 2004.

Vinyl may have just had its biggest sales week ever since 1991 just a couple of weeks ago, largely driven by holiday season spending (and Adele), but don't count out the CD. The compact music format may have been losing pace to the vinyl resurgence in recent years, but 2021 proved to be a significant year for the discs, even as vinyl sales surged 51.4 percent compared to 2020.

The CD's margin of increase wasn't quite as substantial at a lowly 1.1 percent — 40.59 million CDs sold in 2021 vs. 40.16 million in 2020 — but upward momentum, as little as it may be, is better than a continued downslide, especially as music fans keep leaning on streaming platforms such as Spotify, Apple Music and more in their listening habits.

Much like vinyl's big sales week less than a month ago, the increase in CD sales last year was aided by the November release of hit singer-songwriter Adele's new album, 30. It was the biggest album of 2020 in regards to sales as she claimed the top spot for most CD, vinyl and digital sales.

30 accounted for 2.15 percent of all CD sales last year and the 898,000 copies sold alone make up more than the difference in total CDs sold in 2021 compared to 2020. In fact, it was more than double the difference, so, it can loosely be suggested that CD sales would have had an 18th consecutive down year. Other factors, of course, contributed to the banner year though.

To additionally frame just how massive Adele's last record was, the second best selling CD of 2020 was Taylor Swift's Fearless (Taylor's Version), which moved 263,000 copies in all... and it was released in April, more than seven months prior to the release of 30. Swift actually had three albums amid the 10 best-selling CDs in America last year and the total combined sales of those three still did no surpass the total of 30.

Unsurprisingly, no rock or metal acts graced that top 10 chart.

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