In reply to LOL.

It´s been top10 for over a month in sales, and it was top10 in some particular weeks during the last 4 or 5 months. It has become the song for this era. And by giving it this longevity she has given people who are not fans a song to remember from this era, an era with songs hard to sell commercially. They planned it well, stuck to it, and ended prevailing. Who knows maybe they take the song into account for song of the year next grammys :)