The price of crude oil in the U.S. never exceeded $40 per barrel until mid-2004. By 2006 it reached $70, and in July 2008 it peaked at $145. By late 2008 it had plummeted to about $30 before increasing to $110 in 2011. Are speculators at least partly to blame for these sharp price changes? We...

The price of crude oil in the U.S. never exceeded $40 per barrel until mid-2004. By 2006 it reached$70, and in July 2008 it peaked at $145. By late 2008 it had plummeted to about $30 before increasingto $110 in 2011. Are speculators at least partly to blame for these sharp price changes? We...