You'll wonder where the yellow went ...

In what year did this Pepsodent jingle originate?

"You'll wonder where the yellow went when you brush your teeth with Pepsodent"

www.adclassix.com/ classictvcommercials/1948pepsodenttoothpaste.htm has a version from 1948. That might not be the original, but it doesn't seem likely that it could be much earlier.