Barry White is one of those acts with highly recognized hits that never sold large amounts of his studio albums, making him one hell of a candidate for big selling compilations. At that point, the main argument to get into million sales area is the cannibalization factor. In other words, the least compilations have been released, higher sales of those available will be.
Barry White still got several compilations going Top 10 during last 20 years, but a la Bob Marley after 3 to 6 months of promotion, the new hits packages constantly let their place to the perennial bestseller. In the case of Barry White, this one is Ultimate Collection. A smash upon release with 24 weeks inside the Top 5 compilation chart, the album completed 1999 as the second selling hits package behind only All The Way by Celine Dion. It sold about 480,000 units during the year.
With heavy promotion with regular TV spots, the album continued high on charts for many months. It repeated a year end Top 10 placing in the compilation area for a second year, this time at #6, ahead of Greatest Hits by Lenny Kravitz. With about 300,000 copies sold in 2000, the album naturally went 2xPlatinum. In 2001, Ultimate Collection was still a Soul fans favorite, this time placing #25 in year end chart, adding 100,000 sales to its counter. Weirdly, the album barely performed better in 2003 than in 2002 despite the passing of the artist.
In each 2004 and 2008 new hits packages got successful, but each time Ultimate Collection quickly took over the catalog appeal of Barry White. Selling first about 30,000 units per year in early 00s to about 10,000 units now, the album added roughly 185,000 since 2002, putting it over 1 million copies overall.
Net shipment as of the end of 2015 is estimated at 1,065,000 copies.
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Sources: SNEP, IFOP.