(a) (top left) Correlation of ownership of English bulldogs in UK 2008/9 with the GDP of Japan 2008/9; (b) (top right) Correlation of global rise in sea level with the price of butter; (c) (bottom left) Correlation of percentage of international passengers at Heathrow Airport with the popularity of the board game Monopoly; (d) (bottom right) One's personal happiness quotient playing PnF |