Passage: By early 2016, the album had sold 1 million copies worldwide.1000 Forms of Fear's lead single, "Chandelier" was released in March 2014. The song peaked at No. 8 on the US Billboard Hot 100, becoming Sia's first entry on that chart as a lead artist. Elsewhere, the song experienced similar commercial success, ranking in the top ten of the record charts in Australia and numerous European regions. As of January 2015, the single had sold 2 million copies in the United States. "Eye of the Needle" and "Big Girls Cry" were released as the second and third singles from the album, respectively, in June 2014.

Question: How many copies did Sia's song sell as of January 2015?
2 million