Just because it is called an annual fund, that does not mean donors should be asked to give only once a year.

That is the lesson of a newly released survey of annual funds run by colleges.

Public institutions fared much better than private institutions in attracting donors who give year after year: The amount collected from donors who made repeat gifts rose by a median of 11.5 percent, while private colleges increased such donations by a median of 7.1 percent.

Shaun Keister, a fund raiser at the Iowa State University Foundation who wrote a report that accompanied the survey, thinks he knows why public universities are seeing better returns: Based on his experience consulting with other colleges and universities, he says, “ the publics have been quicker to adopt aggressive fund-raising tactics with their annual funds.”

Instead of seeking donations just one a year, many solicit at least twice during the year. They also review how much a donor gave the previous year and ask for a much bigger amount the following year, he says.

The study of college fund raising was conducted by Target Analytics, a Boston research company. It examined annual-fund contributions from 2005 to 2007 at 37 private and 27 public institutions.

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