I suppose that after looking at something closely for a long period of time, virtually anyone would perceive a small change in it as huge. This is reflected in how people formulate graphs. In particular, typically only a small interval is shown, the perceptual impact of which is that small changes look big. For example, Msnbc.com reported on June 8, 2011 that the price of oil “soared” on that day “almost $2 to near $101 a barrel.” My reaction in reading the report was that the word “soared” indicates a lack of perspective on Wall Street and the media.
The full essay is at "Exaggerating Market Volatility."
