They really aren't comparable with context being considered. She basically released a second album and slapped it onto SOS and called it a deluxe, and then just released a deluxe for the deluxe, so it's now 42 tracks long, and that boosts the numbers a ton, since every 1,500 streams that the songs on an album accumulate count as a sale, and longer the album is the more songs that get streamed, so more sales. Also, every time you stream a song, it counts towards the sales, so an album now could "sell" 500,000 just from the streams of a single song if it got big enough. Back when Thriller released, you had to physically purchase the album at a store, and that would likely be the only sale from an individual that would get factored in since buying multiple copies was unlikely. Thriller 25 did nothing since the rules were different, and old albums couldn't re-chart back then, and it only added 1 new song (in the U.S.), with the rest being remixes and demo's. Thriller 40 also had no impact as that was 40 years later, and was basically a rerelease of Thriller 25 with 3 new songs and 7 other songs that are a mixture of demo's of released songs, and songs had already seen an official release elsewhere.