Charitable contributions to U.S. colleges and universities reached $28 billion last year, up 9.4% from the year before, a survey says. It adds that alumni giving, which represents about 30% of such support, grew by “an impressive 18.3%” last year, to $8.4 billion. Though the percentage of alumni making contributions declined, the value of the average gift has increased, from $971 in 2005 to $1,195 in 2006.