Wealthiest Donors Gave 9 Percent of Their Income in 2007, Study Finds

* Donors with master’s and bachelor’s degrees gave the most, while those with doctorates or professional degrees or without college degrees gave the least.

* Wealthy people, like all Americans, volunteered less in 2007 than they did two years earlier. Seventy-percent of affluent individuals lent their time to charities, a 15-percent drop.