How united are we as a society? You can find out at the piano bar

Piano bars may just be the place to learn about what the most popularly requested songs say about the evolving politics in our society. That's pianist Jesse Rifkin's theory.

He's performed in a piano bar in Washington, D.C., for several years and has noticed an interesting pattern in demographic trends when it comes to the songs people request for him to play.

Rifkin expands on his theory with Here & Now's Celeste Headlee.