The first is a unit of purchasing power.

ECONOMIST: The UN's Millennium Development Goals

The second is a unit of currency, which has varying purchasing power depending on where it is spent and what it is spent on.

ECONOMIST: The UN's Millennium Development Goals

Merrill has been actively building its banking unit but could get a big boost by purchasing a commercial bank.

FORBES: Magazine Article

The Times gave several examples of buildings where an apartment owner will see the taxes on their unit triple and quadruple forcing buyers to demand lower prices when purchasing the property.

FORBES: High End New York Apartment Prices Tumble With Wall Street Layoffs