As hospitals throughout the city struggle with financial solvency, a new study of Cornell University’s economic impact casts its medical branch as powerhouse that contributed nearly a billion dollars to the city’s economy in 2005.

Weill Cornell Medical College and Weill Cornell Graduate School of Medicine contributed $966 million to the city’s economy through the employee payroll, money spent on goods and services, and construction, according to the study released yesterday by the consulting firm Appleseed Inc. Juxtaposed against the plight of beleaguered hospitals in New York City, Weill Cornell is an “economic force” in New York City, Cornell’s executive vice president of finance, Stephen Golding, said yesterday.

Among the study’s highlights were the number of employees living in the city, and patient revenue achieved, Mr. Golding said. In 2005, 72% of Weill Cornell’s 4,962 employees lived in New York City. That year, physicians treated nearly 270,000 patients, generating $341 million in revenues.

In addition to those measures, the study also documented $318.9 million in expenditures in 2005, including $118.3 million to New York City vendors. Major purchasing categories included rent and support services, ranging from $9.5 million in lab supplies and equipment to $2.5 million in office supplies. On top of that, the study cited a ripple financial effect achieved through employee and vendor spending. In 2005, employees residing in New York City accounted for $230 million in economic activity and 1,245 full-time jobs.

At a time when city hospitals are facing financial hardship, the study underscores Weill Cornell’s apparent financial achievements, particularly in mirroring the city’s real estate boom. In 2005, it spent $90.5 million on construction, and the report projected that Weill Cornell will spend about $214 million on construction this year.

As recently as two weeks ago, the medical college opened its new Ambulatory Care and Medical Education building, a 338,000-square foot complex on York Avenue at East 70th Street. Future projects include an expansion of its E-building on East 68th Street, scheduled for completion this year.

“Our doctors have continued to do extremely well in a very difficult economic environment,” the dean of the medical college, Antonio Gotto, said yesterday, linking the college’s success with its ability to attract top researchers, doctors, and students.

Cornell officials said the university commissioned the study to assess the school’s contributions and to identify opportunities for improvement. Because Cornell is the federal land-grant university for New York State, the study was also seen as an accounting of the institutions, officials said.