 However, some who have been involved with clap notes for several decades believe that clap notes first appeared in the late-1970s.To put this in perspective it is necessary to recall that in the late 1960s to early 1970s the main influences on the U.S. economy were the Vietnam War and the Watergate Scandal.The super-inflation of the period resulted in returns of as much as 17% on CDs, while the stock market was taking a plunge.