About two-thirds of U.S. grandparents have helped support their grandchildren financially during the past 5 years, researchers report.

Grandparents gave an average of $8,661, or a total of almost $371 billion, to help support their grandkids over that period, according to the MetLife Mature Market Institute, a unit of MetLife Inc., New York.

Institute researchers hired a firm to poll 1,077 U.S. adults ages 45 and older who have grandchildren ages 25 or younger.

About 40% of the financial support participants gave was for general purposes and 26% for education, institute researchers report.

The institute’s 2009 Grandparents Poll found that grandparents would rather help their children and grandchildren while they are alive, rather than leaving a lump sum in a will.

The economic downturn has caused 25% of the participating grandparents to increase the financial help they are giving to their grandchildren. Those with lower incomes and lower net worth are giving a higher percentage than they did before the most recent economic downturn, with 22% reporting that their generosity has hurt their own financial situation.

Other information gleaned from the 2009 Grandparents Poll:

- Those grandparents with at least a college degree are more likely than those without a degree to support education, with 37% of the grandparents with college degrees helping to pay for education, compared with 24% of the grandparents without degrees.

- 46% of the participants have set up a college fund, while 26% are paying for pre-college expenses and 24% are helping with college tuition or loans.

- 83% of the givers are giving cash.

- 30% of the participants have encouraged or have spoken to their adult children about life insurance as a way to protect the future of their grandchildren.