One of the most popular albums in the United States, Taylor Swift’s 1989, is about to lose significant market share to a newer version, Swift’s re-recorded 1989 (Taylor’s Version).

It’s happened three times before. 1989 (Taylor’s Version), a re-recorded and expanded version of the nine-times platinum 2014 album, with five previously unreleased tracks, follows the insanely successful formula of the three preceding albums: Fearless, Red and Speak Now. If 1989 (Taylor’s Version) enjoys the same trajectory as its predecessors, the Big Machine-era version of 1989 will lose a majority of its weekly consumption and forever get crowded out by the more popular, Swift-endorsed re-recordings.

To understand what could happen to 1989, consider its predecessor, Red. Average weekly consumption of Red — measured in equivalent album units, which combines physical and digital album sales, track sales and streams — dropped 40% in the 12 weeks following the release of Red (Taylor’s Version), according to Billboard’s analysis of Luminate data for the United States. The original version of Speak Now took an even bigger hit, losing 59% of its average weekly consumption in the 12 weeks after the re-recordings were released. Given those two trajectories, the original version of 1989 could very well lose half its average weekly consumption.

Consumption of the original 1989, which includes Hot 100 chart-toppers “Shake It Off” and “Bad Blood,” has soared this year as Swift reached a Michael Jackson-level of media coverage. As Swift Mania heated up, thanks to her record-setting Eras Tour and steady output of new and rerecorded material, 1989’s average weekly album equivalent units (AEUs) climbed from 16,000 in January to 29,000 in May to 39,000 in August, peaking at 46,000 in the week ended Aug. 17. On the latest Billboard 200 albums chart, the original 1989 ranked No. 20 — one spot behind Speak Now (Taylor’s Version) and two spots ahead of Reputation, Swift’s final album for Big Machine.

That has been great news for Shamrock Holdings, which acquired Swift’s Big Machine master recordings in 2020 for a reported $300 million. In the year before Shamrock Holdings acquired Swift’s catalog, 1989 averaged about 10,000 AEUs per week — 70% below the current level. While Swift’s previous three albums of re-recordings ate into the Big Machine originals, 1989 was spared and got to benefit from Swift’s success — that is, until she got around to releasing her Taylor’s Version.

The original version of 1989 — Swift’s best-selling album to date — has more to lose than its predecessors: 1989 has averaged 33,000 equivalent album units over the previous 12 weeks, nearly 1.8 times more consumption than the 19,000 AEUs Speak Now averaged in the 12 weeks before Speak Now (Taylor’s Version) was released. The original versions of Fearless and Red had even less consumption in the 12 weeks before Swift’s re-recordings came out: 7,000 AEUs for Fearless and 9,000 AEUs for Red.

If 1989’s weekly AEUs drop by 50%, Billboard estimates the gross sales from purchases and streams will drop by nearly $120,000 per week — equal to more than $6 million per year. That’s gross sales, not wholesale. Shamrock pockets less than wholesale after paying royalties, distribution and manufacturing.

And if 1989 (Taylor’s Version) performs like the other three albums of re-recordings, it will far outperform Swift’s Big Machine originals. Through the first 41 weeks of 2023, the re-recordings of Fearless and Red have respectively averaged 4.8 times and 4.1 times the weekly consumption of the original albums. Speak Now (Taylor’s Version), which has just 14 weeks of sales history since its July release, currently has 5.3 times the average weekly consumption of the original.

The original version of Reputation also has a lot to lose. In the past 12 weeks, Reputation has averaged 27,000 AEUs per week. And just as 1989 consumption skyrocketed this year, Reputation’s weekly AEUs have more than doubled since January. Shamrock Holdings will enjoy those spoils, too -- that is, until Reputation (Taylor’s Version) inevitably arrives.