Adele was still viewed as a “developing artist” when 21 was released as the follow-up to her well-received 2008 debut LP 19 on 2/22/11. The album immediately ignited, debuting with 352k in sales, supercharging sales and airplay on the irresistible lead single, “Rolling in the Deep” (which would go on to sell 8.4m+ in the U.S. alone). At that point, Columbia knew that its sky-high expectations for the album were beginning to come to fruition, and the label’s marketing and promotion teams pushed the pedal to the metal.

21 sold consistently throughout 2011, averaging around 150k a week—but didn’t reach critical mass until the gift-giving season. It became truly massive following the 2012 Grammys, which Adele dominated with a record-tying six awards, including Album of the Year for 21, transforming Music’s Biggest Night into the coronation of the new Queen of Pop.

The graph below traces the album’s momentous first 13 months, airplay milestones on the four singles embedded into the timeline. The RTDs and peak sales weeks of these singles, plus those of 2012’s James Bond theme song, “Skyfall,” and the first week of current single “Hello,” are contained in the box that follows the copy.

There is a parallel story here: that of 19, as its follow-up was making its gradual climb throughout 2011 and into 2012. Adele’s debut LP had sold around 600k by the time 21 dropped. Subsequently, 19 topped 25k just seven times during the period charted below and climbed above 50k only twice. It has never sold over 100k in a single week. If the album had been included on our graph, it would appear as a virtually flat line. But slow and steady wins the race—or was at least good for second place in this case: Nearly six years after its release, and without a high-charting stateside single—“Chasing Pavements” peaked at #21—19 has sold just over 2.7m in the U.S. And that total will inevitably get another boost from the release of 25 as it begins its history-making journey.