It's a link to a site that will tell you what the number one selling song was in the country the day you were born (or the day you got married or the day you first ate creamed corn or any other date you enter).
On the day I was born, "Heart and Soul" by Larry Clinton, was the number 1 song.
On the day I was married . . ."Cathy's Clown," by the Everly Brothers