I like Leonardo DiCaprio’s facial expression when McConaughey starts doing the humming and the chest thumping. I’m guessing there are a lot of young traders on Wall Street watching this clip over and over, right. Actually, I’m guessing there quite a few traders of all ages watching this clip and the entire The Wolf on Wall Street movie over and over.
Where does Matthew McConaughey’s chant or humming come from?
Before certain scenes in the film, and his other films, McConaughey does this to relax. After five takes of that particular scene, Scorsese was ready to move on, but Leo DiCaprio asked McConaughey about his chest thumping. Leo suggested they do another take to include that and it was eventually included in the final cut. (Quora)
And I bet this scene is being played over and over too – the delayed reaction of those Lemmon Quaaludes.