Nonprofit hospitals, originally set up to serve the poor, have transformed themselves into profit machines. And as the money rolls in, the large tax breaks they receive are drawing fire, the Wall Street Journal reports.

Riding gains from investment portfolios and enjoying the pricing power that came from a decade of mergers, many nonprofit hospitals have seen earnings soar in recent years. The combined net income of the 50 largest nonprofit hospitals jumped nearly eight-fold to $4.27 billion between 2001 and 2006, according to a Wall Street Journal analysis of data from the American Hospital Directory. AHD, an information-service company, compiles data that hospitals report to the federal government.

The Cleveland Clinic swung from a loss to net income of $229 million during that period. No fewer than 25 nonprofit hospitals or hospital systems now earn more than $250 million a year. One nonprofit hospital system, Ascension Health, has a treasure chest of $7.4 billion — more than many large, publicly traded companies.

Nonprofits, which account for a majority of U.S. hospitals, are faring even better than their for-profit counterparts: 77% of the 2,033 U.S. nonprofit hospitals are in the black, while just 61% of for-profit hospitals are profitable, according to the AHD data.

At some nonprofits, the good times are reflected in new facilities and rich executive pay. Flush with cash, Northwestern Memorial Hospital in Chicago has rebuilt its entire campus since 1999 at a cost of more than $1 billion. In October, it opened a new women’s hospital that features marble in the lobby, birthing rooms with flat-screen televisions, 1,000 works of art and a roof topped with 10,000 square feet of gardens. In 2006, Northwestern Memorial’s former chief executive officer, Gary Mecklenburg, received a $16.4 million payout.

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