U.S. residents spent about $2.3 trillion on health care in 2007, or 16% of its gross domestic product, according to the Blue Cross and Blue Shield Association.

U.S. health care spending has increased from $2.1 trillion, or 16% of the GDP, in 2006, according to the BCBSA, Chicago.

The BCBSA predicts national health care expenditures will increase by more than 70% between 2007 and 2015, to almost 20% of the GDP.

The association also reports the following data in its 2008 Medical Cost Reference Guide:

- Since 2002, the number of uninsured U.S. residents has increased at all income levels.

- About 50% of uninsured Americans cannot afford coverage.

- The leading causes of death are also the most costly. In 2004, more than 147 million people had one of the 5 most expensive conditions, and treating those conditions cost more than $311 billion.

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