Two key U.S. senators sent a letter to 136 colleges and universities on Thursday requesting detailed information on endowment spending, tuition costs, and financial-aid policies over the last decade, reports The Chronicle of Higher Education.

Sen. Max S. Baucus, Democrat of Montana, and Sen. Charles E. Grassley, Republican of Iowa, announced plans to send the letters just a few hours after the release of an annual report showing that college endowments earned an average return of 17.2 percent in 2007. Colleges with endowments of at least $500-million as of June 30, 2007, are to receive the 50 questions.

The senators say that since university endowments receive large tax benefits, these institutions must prove how they are working to keep the cost of tuition down for students, particularly those from low- and middle-income families.

“Tuition has gone up, college presidents’ salaries have gone up, and endowments continue to go up and up,” Mr. Grassley said in a written statement. “We need to start seeing tuition relief for families go up just as fast.”

Colleges have expressed a mixed reaction to the letter, but many are concerned that 30 days is insufficient time to respond. Robert J. Birgeneau, chancellor of the University of California, told The New York Times that “I believe that Senator Baucus’s and Grassley’s intentions may be admirable, but understanding university finances is an extremely complex matter, especially in public colleges and universities.”

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