16. Houston's version of "I Will Always Love You" sold 12 million copies, making it the best-selling single ever by a woman. Her recording topped Billboard's Hot 100 chart for a then-record-breaking 14 straight weeks. It also sold millions of downloads in the days after Houston's death in 2012, for a total of 20 million units sold. "I knew I had sung the s**t out of it," Houston said in 1993. "But I had no idea that that record would sell so much, so fast".
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