As always, individuals accounted for the largest share of charitable donations. In 2011, they accounted for 73 percent of giving. When bequests and family foundations are added, American households donated 88 percent of all charitable giving.
Americans are parting with a lower share of their incomes than they did during the good times. The 1.9 percent of disposable income shared in 2011 is down from 2.4 percent in 2005. (The study doesn’t break out the income or wealth levels of the givers, so it’s tough to know the comparable giving rates of the wealthy).
"People have had to make tough decisions about how they spend their money, and many have had to reduce the portion of their budget that goes to charity below what they normally give,” said Patrick M. Rooney, executive director of the Center on Philanthropy, which co-authored the research.
When it comes to where they gave their money, Americans tended to focus on human services and international aid. They gave less to arts groups and churches.
Here are the amounts given to each category:
RELIGION: Total giving to religious organizations totaled $95.88 billion in 2011, down nearly 5 percent in inflation-adjusted terms.
EDUCATION: Giving totaled $38.87 billion in 2011 for education, which was flat with 2010 when adjusted for inflation.
FOUNDATIONS: Giving to foundations fell 9 percent, adjusted for inflation, to $25.8 billion.
HUMAN SERVICES: Donations increased only slightly for human services and totaled $35.4 billion. But the total levels were the third highest ever recorded for the category.
HEALTH: Donations total $24.75 billion to health-related groups, roughly flat with last year.
INTERNATIONAL – Gving to international affairs grew 4 percent in inflation-adjusted terms, to $22.7 billion. This sector has grown much faster than the overall charitable giving sector since 1987.
ENVIRONMENT: Giving to environment and animal groups rose 1.4 percent in 2011, reaching $7.81 billion.
-By CNBC's Robert Frank
Follow Robert Frank on Twitter: @robtfrank