As lower costs encourage firms to produce more at any given price (ie, the supply curve shifts from S1 to S2 in the chart), the long-term equilibrium level of output will rise and the price level will fall.

ECONOMIST: A thinkers’ guide | The

The supply of skilled workers has failed to keep pace with demand, so the college wage premium (see chart) has increased.

ECONOMIST: The middle-class task- force

This chart illustrates the interconnectivity of gold and global money supply growth.

FORBES: Move up http://i.forbesimg.com t Move down

Money-supply growth still looks sluggish in Britain, Japan and the euro zone (see chart).

ECONOMIST: Buttonwood: Pausing for breath | The

OPEC, which is dominated by Middle Eastern producers, owns three-quarters of the world's proven reserves (see chart), it currently produces only 41% of the world's annual oil supply.

ECONOMIST: Oil��s well that ends well