Courtesy of my advisor, Shmuel Weinberger
Changing yen to dollars
A Japanese man was travelling in America and needed to exchange
some yen for dollars. At the bank, he handed enough yen to get
100 bucks. The next day, he went to the bank again, and gave
the same number of yen, but only received 95 dollars. Upset, he
asked the teller, "Why do i only get 95 dollars?"
She responded, "Fluctuations."
The Japanese man was very very upset, and went outside onto the
street and yelled, "Well, Fluck You Americans!!"